“My name is Dr Owen Harper and this is my life. A life that’s full of action, violence, work, wonder, secrets, sex, love, heartbreak, and death. My death - the death I survived, the death I’m now living through. Except this isn’t living. Every day is the same. I get up, get ready for work, the same as everyone else. The thing is, I’m not the same. I get to work and everyone’s doing the same old thing, babbling away about aliens and weddings. I’m not real. Three days ago I died and they think I’m fine. But they’re wrong!”

At the top of a high car park in the centre of Cardiff, two lone figures sit silently on the edge of the parapet and look out over the city. Then Owen turns to Maggie, the woman sitting next to him, and asks if she’s ready to jump. She tells him to piss off and get off her roof. She tells him she’s going to jump and thinks he should leave her alone. He assumes her boyfriend has probably just dumped her, but she becomes angry and tells him she’s not interest in his opinions. He assures her he’s not here to stop her and if she thinks she’s got problems, she should see his. Maggie is shocked when he shows her the gaping wound in his chest where he was shot. At first she doesn’t believe him, but the truth dawns on her when she sticks her finger inside the hole. She climbs down from the edge and backs away from him nervously. She asks him who he is and he tells her he’s dead. She knows that can’t be true because he’s standing there, talking and moving, but he tells her he was brought back. She asks him what it’s like being dead and what delights has she got to look forward to. Owen tells her it’s just darkness, nothing else.

Much earlier, Jack Harkness relieves Owen of his position at Torchwood and orders him to hand over his weapon and security pass. Owen argues that he’s fine, but Jack says he died three days ago and he needs to be examined. They need to find out what he is and be certain that he‘s okay, and until Jack is confident he’s fit for duty, Martha Jones will replace him as Torchwood’s medical officer. Owen asks what they’ll do if he refuses to undergo the tests and Jack tells him he’ll be confined to the cells and the tests will be done anyway. If the results show he’s a danger to the rest of the team, appropriate steps will be taken. Jack softens and pleads with Owen to let them help him. Reluctantly, Owen passes his gun and documents to Ianto. He asks how long the tests are going to take, but all Jack can say is they’ll last as long as they need to. Owen wonders what he’s supposed to do in the meantime and Jack tells him they always need someone to make the coffee. Ianto and Owen are equally horrified.

Ianto teaches Owen how to make the perfect coffee. He hands a fresh cup to Owen, but snatches it back quickly when Owen reminds him what happens when he drinks these days. Owen tries to copy what Ianto showed him, but he has trouble with the equipment and becomes frustrated. Ianto asks if he’s okay, but Owen suspects he’s really loving all this and he must feel like he’s won. Ianto says he didn’t realise they were in competition, but Owen snaps back and says even Tosh had more of a life than Ianto used to. But now Ianto’s joining them on missions and shagging Jack, while Owen’s going to be stuck here making the coffee. Owen thinks his life is nuts. He says Ianto has Jack, Gwen’s getting married, Martha’s got a bloke and even Tosh had Tommy. Ianto reminds him they’ll all had their fair share of nuts. He’s seen Owen dissect alien corpses and save so many lives and asks him if he’s really going to let this beat him?

Martha begins her tests on Owen. She monitors him as he exercises on a running tread and then later with weights. He teases her and suggests she’d rather spend time with him than with her own boyfriend, but she assures him he has nothing to worry about, nor is she after his job. She confirms that there’s no sign of any muscle decay and he’s in great shape. She asks him if he’s had any stiffening anywhere and although he teases her again, he tells her there’s no evidence of rigor mortis. She tells him there’s no trace of any further cell mutation and he’s 100% human again. If he keeps up the exercise he won’t atrophy and as an added bonus, it looks like he’ll never age either. Gwen calls and asks Martha to join the others in the boardroom. Owen is resigned to the fact that he’s been downgraded to fetching the coffee for everyone.

In the boardroom, Jakes briefs Gwen, Tosh, Ianto and Martha on their next mission - to investigate local millionaire Henry John Parker. He used to be a looker, apparently, but he’s now in his eighties and even Jack has his limits. Parker is a collector of alien artefacts and has been on their radar for a long time, but until now he’s been filed in the ‘mostly harmless’ category. However, this morning Tosh detected a huge energy spike coming from Parker’s house and it’s something they’ve never seen before. Owen arrives with coffee for everyone but he gets their order wrong and while he’s not looking they all exchange mugs. Gwen says Parker’s never been regarded as a threat and he has a reputation as a ‘Howard Hughes’ type as he hasn‘t left his house since his wife died and nobody’s seen him since 1986. Owen sits at the table and tries to join in the discussion, but there’s an embarrassed silence as everyone turns to look at him. Then Ianto teases Owen for his morbid fear of the character Tintin. Owen explains that he has a funny face and horrible hair and he never had a girlfriend. In fact, Owen thinks Tintin was probably shagging his dog. The ice has broken and the rest of the group seem to accept Owen’s presence at the table. Gwen reminds them they need to check the alien energy pulse out. She asks Tosh to get a complete schematic of Parker’s house, then she asks Ianto to get an inventory of every artefact that Parker has bought over the last ten years and asks Martha to see if she can get hold of his medical history. The group split up and as they leave, Gwen shares a joke with them about how the wedding arrangements are going so far. Jack notices that Owen is sitting alone, having been given no duties on this mission.

On the car park roof, Owen tells Maggie that nearly a million people kill themselves worldwide each year, which is nearly three times the population of Cardiff. Maggie thinks he must be some sort of suicide geek and is surprised when he tells her he’s a doctor.

As he casually starts flicking a scalpel in his hand, Owen tells Martha that he’s a bloody brilliant doctor, so he wonders why she’s doing his job? She explains that he needs help and says that’s not a bad thing. He tells her he’s finding it frustrating having to make the coffee and tries to tempt Martha into returning to her boyfriend, but just as he’s assuring her that’s he’s perfectly fine, she notices that he’s sliced his hand open with the scalpel. She begins stitching the wound, but warns him it’ll never heal so he‘s going to have to re-stitch it himself every week or so. He didn’t feel a thing, so at least he won’t need anaesthetic, but it bothers him that he can’t even feel the needle and thread, let alone Martha’s hand holding his. He can be aware that he’s holding things, but he’ll never feel anything again. She warns him that his bones will never heal if he breaks them and even bruises will never recover. In short, he’s fragile.

Maggie wonders why Owen keeps pushing away people who are trying to help him and he admits that he doesn’t follow the social niceties any more, not that he ever did when he was alive. Owen thinks Maggie is a pain and wonders if this is why her man dumped her - but he regrets saying that when she tells him he died. Owen apologises but she knows he couldn’t care less about her and she doesn’t care about him either. Just because they’re both planning to kill themselves, it doesn’t mean they have any connection.

In the Hub, Owen continues to provide regular coffee supplies and everyone politely ignores the fact that his hand is now bandaged. Eventually he pleads with Jack to give him something meaningful to do, but Jack says he can’t. Owen says he might as well go home then, and Jack agrees without any argument, which makes Owen feel worse. He asks what he’s supposed to do when he gets home and Jack suggests he watch TV and chill. Owen reminds him that he’s dead and is permanently chilled. He finds it ironic that Jack gets to live forever, but he only gets to die forever.

Owen spends the rest of the morning at home watching daytime television and his eyes start to glaze over almost immediately, as if his brain is being sucked dry. Eventually he gets up and decides to clear his flat of things he’s never going to need again. He begins by emptying the fridge of all food and drink, then he clears out the toilet and bathroom. Then he removes all the fruit from the bowls in the living room and returns to the settee to watch more daytime television. He goes to the empty fridge and looks inside longingly, then he sits alone, silently contemplating for what seems like an eternity. Eventually the doorbell rings and he opens the door to find Tosh outside. She joins him inside and says she’s starving. She’s brought some food and asks if he minds her eating. He assumes Jack has asked her to come round to encourage him to ‘open up’, but she says she’s here because she’s had a really bad morning. She launches into an unending tirade about how Jack’s been treating her and about not being asked to be Gwen’s bridesmaid. Owen begins to switch off mentally and Tosh’s voice becomes a distant monotone, fading away slowly until he’s no longer listening to a word she’s saying.

From Owen’s description, Maggie think he and Tosh sound like an old married couple and it reminds her that Brian used to say she talked too much as well. Owen asks her to tell him about Brian and she reveals that today is their wedding anniversary. She remembers the moment when she and Brian emerged from the church and were covered in confetti. It was her perfect day. She then remembers standing frozen in the middle of a motorway, still wearing her wedding dress but now covered in blood. She tells Owen there was an accident. She remembers staggering back to the upturned car and looking at her dead husband’s body inside. They’d been married less than an hour. She remembers walking back down the motorway, in a complete state of shock. She says she was picking confetti out of her hair when it happened. Owen tries to say he’s sorry, but too many people have told her that already. He asks why she waited until their anniversary to kill herself and she says it was because she believed people when they told her it was going to get better. She asks Owen whether he thinks it will ever get better for her, but he doesn’t answer and they both look out again across the night skyline of the city.

Back in his flat, Owen remains silent while Tosh completes her account of the day, unaware that he hasn‘t been listening to anything she’s said. Then Owen suddenly comes to his senses and asks Tosh exactly what she’s doing here. She says she wants to help him and he asks her how she intends to do that. He doesn’t believe her and says that for some reason, she wants him. All this time she’s watched him screwing other women while her own heart was breaking, but it’s different now because he’s safe and cosy. Tosh folds her arms and refuses to leave, but Owen says she probably regards this as the date she always wanted. The only thing that’s missing is the pool table. Tosh retaliates and asks what’s wrong with him and he tells her he’s got no heartbeat and no feelings, so he’s got nothing to give her any more. He wonders if that’s what she wants - someone who’s just as twisted and screwed up as she is. He asks if she wants a demonstration of someone who’s broken - and he proves his point by bending back one of his fingers. Although he doesn’t feel any pain, he’s shocked by what he’s just done and runs from the flat in horror.

Owen races through the nearby park and heads for Cardiff Bay. Then he runs at full pelt down the wooden harbour arm and leaps straight into the water. He stays underwater for what seems like ages - then opens his eyes and realises he’s wasting his time as he doesn‘t need to breathe. Eventually he pulls himself out of the water and lies on the harbour. Jack appears and checks his wrist-strap before telling Owen that he’s been under for 36 minutes. He asks Owen how long this is going to go on for, but when he gets no response, he turns and heads back for the Hub.

In the boardroom, Gwen gets updates from the others. Ianto has identified some of the things Parker has purchased recently including a Dogun eye, some meteorites and an alien translation of James Herbert’s ”The Fog” - but there are also a few things they’ve never seen before and one of them must be causing the energy spike. They’re getting dangerously bigger, so Gwen decides they need to get into the house straight away. They’ve learned that Parker employs a man called Philip Farrington to run the security and there are at least six guards and a full CCTV system protecting the estate. Gwen knows they can overcome all of this by taking down the generator, but there are also solar powered heat sensors at every door and window which can detect any form of body heat. The group ponder how they’re going to get past them when Owen arrives and says it sounds like they need a dead man. He asks Jack what they have to lose by trusting him and eventually Jack agrees. Ianto hands over Owen’s gun just as Tosh returns to the Hub. She and Owen look at each other uncomfortably for a moment, then she hands him his flat keys and says she turned his telly off before she left.

Maggie can’t believe the way Owen has treated Tosh. He screamed at her and said all those awful things and she didn’t complain once. Owen says that’s what Tosh is like - she’s always professional. Maggie turns on him and says she’s not interested in his story, or hearing about old men and alien meteors. She says she came here because her husband died and she just wants to jump. Owen grabs her and physically drags her right up to the parapet. As they look over the edge, he tells her he knows she’s too scared to do it, and she asks if he is too. She wants to know how he ended up here, so he tells her the rest of the story…

Owen prepares to break into Parker’s house and establish the cause of the energy spikes. After bandaging his broken finger, Martha warns Owen again that he won’t recover from any injuries he receives, so he must avoid all physical contact and act as though he’s made of glass. She and Jack wish him luck, then he sprints to the boundaries of Parker’s estate. A high wall surrounds acres of land which includes a large house and swimming pool. Owen arrives at a locked gate and peers inside to see two security officers patrolling the area. Tosh contacts him and tells him the power for the house all comes from one privately owned generator. There’s a backup unit, but if he can take the main one down, he’ll have one minute and twenty seconds of blackout time in which to enter the house. Owen asks if they can get rid of one of the guards for him - preferably the big one - and seconds later, he hears a mobile phone ringing. Gwen has obtained the names and telephone numbers of the security guards and calls one of them, Mr Taylor, to inform him that his wife has been involved in a minor traffic accident and has been taken to hospital. Owen watches as the man takes the call then tells his larger colleague what’s happened. The remaining guard then contacts their boss, Farrington, to brief him that they’re a man down. Owen takes cover as the guard approaches the gate and exits, then Owen slips through into the grounds before the gate closes.

Owen moves silently but swiftly through the grounds and eventually makes his way to the power generator outside the house. He opens it up and is about to sabotage it when the large guard returns and catches him red handed. He orders Owen to move away, but Owen lashes out and knocks the guard to the ground. He pulls a gun on the guard, then, wrapping his hand in a T-shirt that his colleagues provided for him (humorously featuring an image of Tintin and his dog) Owen reaches inside the generator and pulls out several of the cables. Ignoring the sparks of electricity, Owen disables the equipment and all the lights in the house and the grounds go out. Knocking the shocked guard unconscious, Owen races towards the nearest door as Tosh begins the countdown of one minute, twenty seconds. They hear the voice of Farrington contacting the guards to tell them to stay at their posts as the backup power will be available in forty-five seconds. Tosh apologises to Owen and says that improvements must have been added recently.

Owen opens a side door into the house and stops as he sees a heat sensor planted discreetly at floor level. Fortunately this is no longer a problem for him and he waves his hand across the sensor several times to confirm that it can’t pick up any body heat from him. Then he begins to move through the house, checking each room carefully before following Tosh’s directions to the area where the energy readings seem to be coming from. He needs to make his way to a room at the back of the house on the first floor, but before he can do so all the lights in the house come back on.

He arrives at the bottom of the main staircase and slowly starts to walk up. Almost immediately a guard appears at the top of the steps and orders him at gunpoint to stop. Owen greets the man and compliments him on the beautiful house. He starts to walk up the steps towards the guard, refusing to stop or to answer any of the guard’s questions. The man threatens to shoot, but Owen knows he’s bluffing. He’s just a security guard and the gun is only for show. The guard probably doesn’t even know what a bullet does to a living person. Owen explains the effect in gruesome detail, moving closer step by step until he ends up standing beside the guard at the top of the stairs. Owen tells the guard that he has no body heat because he’s actually a dead man - and in the moment of confusion, he snatches the guard’s gun and knocks him unconscious with his own weapon.

On the first floor Owen moves down a long corridor towards the room at the back of the house. Inside, he finds glass cabinets filled with strange alien objects and artefacts. Behind some sliding doors is a huge bed covered with curtains and surrounded by medical equipment. In the bed is the apparently sleeping figure of Henry Parker, but as Owen approaches him, the elderly man opens his eyes and asks what he wants. Owen assures him he’s not here to hurt him, but Parker reveals that he’s been watching Owen all the time via a series of screens showing CCTV footage from all over the grounds. Parker knows that Owen is from Torchwood and asks if the American sent him. Owen confirms that he did and asks the man how he knows so much about them. Parker is disappointed they didn’t sent the Japanese girl instead and, knowing the others will be listening in, he calls out hello to Tosh and tells her she’s got very lovely legs and she should show them off more.

Parker starts to cough and Owen asks what’s wrong with him. Parker says he’s had three heart attacks and a failed bypass, but he’s fine because of an alien device that’s looking after him. From under his bed sheets he produces an object shaped like a rugby ball which is glowing with fierce energy and which regularly emits waves of colourful light. Parker says he calls it the Pulse and it’s keeping him alive. Owen goes to examine it, but Parker pulls it away and says he can’t take it. Owen warns that it could be dangerous and waves a detecting device over it. He tells Parker they’ve been picking up massive energy readings, but Parker doesn’t care and all he’s interested in is the fact that it works. But Owen has a surprise for him - according to the readings he‘s just taken, the energy hasn’t been going into Parker at all. The power is building up inside the device, but it isn’t actually doing anything for the old man. Parker doesn’t believe him and says he can feel its effects, but Owen says too many people’s lives are at risk and if the device explodes they have no idea what the fallout is going to be. Parker tells Owen he’s too young and doesn’t understand what it feels like to be dying, but Owen assures him he does. Parker tells him there’s nothing there on the other side and if they take away his Pulse, he’ll die. Owen sympathises but says it’s going to happen one day anyway and no one can stop it. Parker is worried that it’ll be dark and he’ll be alone, but Owen says that’s exactly the life he’s already leading, alone in his dark bedroom, so what‘s the difference?

The old man begins to go into spasms and Owen quickly pulls an oxygen mask over him. Slowly Parker starts to recover and his vital signs return to normal. He doesn’t understand what’s keeping him alive and Owen tells him it’s hope. The alien device represents hope, but Owen asks if he really believes that life like this is better than death? Parker is sure that it is, but Owen tells him he’s just scared of the darkness. He tells him he knows how it feels, but this angers Parker who thinks he’s just a boy who doesn’t know anything. Parker says he’s travelled the world, fought in the war, set up his own business and made a fortune, got married, became widowed, and started his collection. He’s done so much in his life, but this is where he’s ended up - alone and lying in his own piss. The thing he most wants is a medium rare steak with black pepper sauce, but he’s ended up being fed through a tube. He thinks he might as well be dead already and his comments strike a chord with Owen. In anger, Parker tells Owen he should take the Pulse and be done with it. He hands the still glowing device over and then realises just how dark everything is and how alone he feels. Owen holds his hand and tells him he’s going to come back and the two of them are going to face their problems together. Parker is keen to hear more about Torchwood and the aliens they’ve encountered as he needs to know that there’s more out there. He promises that if Owen comes back, he won’t tell the Japanese girl that they’re still holding hands.

Just then, Parker goes into spasms again and Owen rushes to provide him with more oxygen, but this time it’s not having any effect. Parker’s life signs go into flatline and Owen immediately begins attempts to resuscitate him. He thumps the old man’s chest and then prepares him for mouth-to-mouth - only to realise he can’t provide the necessary breath. Angrily, Owen punches the bed, but there’s nothing he can do and he apologises to Parker.

On the rooftop, Owen explains to Maggie why he was unable to save Parker’s life. This was the final straw. Even though Parker was just another old man dying of a heart attack, Owen feels responsible and that was the moment he decided that he wanted everything to end.

At Parker’s bedside, Owen hears Tosh trying to call him over the communicator. Eventually he responds and she asks him to check the alien device because the energy levels coming from it are going off the scale. She’s convinced it’s going to blow and Owen realises the intensity of the device’s glow is increasing. There’s nothing anyone can do to stop it, but Owen tells them not to worry as he’s going to hold it and see if he can absorb the energy. Tosh warns him he won’t survive, but Owen says that’s okay and these things happen. Martha is sure there must be something they can do, but Owen knows Torchwood is going to need a new medical officer and he thinks she has all the credentials and skills. He pleads with Jack not to even think about bringing him back again, then he tells Gwen and Ianto that it’s been fun (mostly), and he thanks them. Then he speaks to Tosh and tells her he’s sorry. She responds by telling him that she loves him. The energy emanating from the device becomes even stronger and before long Owen, and most of the room, is enveloped in a warm throbbing pink light.

Maggie asks Owen to explain what happened, but he just tells her that although everyone assumes life is going to be shit, sometimes it’s not. He bends down to open a rucksack at his feet and takes the still throbbing Pulse device out. Maggie looks at it in amazement and asks what it is. He asks her if she remembers that NASA were sending messages out into space during the 70s. The messages included maps of the Solar System, pictures of what we looked like, even voices and music. This device is a reply and although they don’t know who it’s from, Owen says it sang to him…and now he knows that sometimes life does get better.

Jack and Martha collect Owen in the SUV and he’s reunited with the others outside the Millennium Centre. Owen is smiling for the first time in ages and he tells Martha he’s sorry but there are no job vacancies here at the moment. She’s about to tell him he’s fine, but she realises he’s a hell of a lot more than that. He thanks her for everything, then he kisses and hugs her. Martha then says goodbye to each of the team in turn, before rejoining Jack and telling him it’s been interesting working with them. He corrects her and tells her it’s been fun. They kiss and he tells her she’s welcome to come back any time. She says she might well do that, one day. Then she picks up her bags and leaves Cardiff.

In the Hub, Tosh asks Owen to promise her one thing - that if things are bad, he has to share it with her. He agrees and admits that he’s scared that if he closes his eyes he’ll get trapped in the darkness. She holds his hand and tells him she’s here for him. Later, Owen is walking home when a piece of paper drops down on him from above. He unfolds it and sees that it’s a photograph of a happy young couple. He looks up to see where it came from and sees a young woman sitting on the parapet at the top of the car park.