Later that evening Kevin is working on his painting. Dominic orders him to clean up, but as he does he spills paint all over Dominic’s trousers. Dominic has to change, but Sir is at the door. After answering without his trousers on and slamming the door hastily shut, Dominic hurriedly puts them on and opens the door again. Sir is affronted that Dominic has slammed the door in his face, but Dominic improvises, explaining that it was the wind, which often blows inside big old houses. When Sir comments that his house is really rather small, Dominic explains that it’s deceptive: “it’s bigger on the inside than it is on the out.” He is then distracted by the feeling that there’s something on the tip of his mind… But it fades, and he takes Sir’s coat and leads him into the house.

Dominic exchanges uncomfortable small talk with Sir as he pours a drink for his boss. Kevin arrives in the living room, and because of his long hair Sir mistakes him for a girl. Dominic apologizes for his son’s behavior, saying “If I could go back in time and not have him, I would.” He then becomes distracted again, seeming to remember a time when he wasn’t frightened of anyone in the universe, and didn’t have a boss or a son. June returns from the kitchen, and the moment passes, though Dominic complains of frequent headaches. Sir is so impressed by June’s looks that he offers Dominic a promotion, provided the meal goes well. He then announces that he is expecting vegetarian food per his doctor’s orders. Dominic panics again but recovers quickly and sneaks out the kitchen, where he uses Kevin’s paint to disguise Sir’s steak as greens. Sir adores the meal, and Dominic’s promotion is assured. Everything has ended happily…

The opening tune plays again as Dominic arrives home once more. June takes his briefcase and umbrella and offers him the paper and a gin and tonic. He drinks, but as he is praising her drink making skills the sound fades out… The tune plays, and Dominic is home again. Everything happens as before, but the sound fades as Dominic takes his drink. He arrives home yet again, but this time pauses as though confused when praising the comforts of home, and when offered his gin and tonic he asks for ginger beer, because he fancies a change. June is at first confused and then frightened. Dominic ultimately accepts the gin and tonic, but June cuts off his praise to go and make a phone call.

Kevin greets his father. His scheme this week is different; even he sees that it’s a terrible idea. He was going to sell carbonated soft drinks like ginger beer. Dominic thinks there might be a market for it, but when Kevin gives him a taste of ginger beer it’s absolutely revolting. To show that it’s mostly bubbles and foam, Kevin shakes a bottle up, and it spills all over Dominic’s trousers. The doorbell rings. Sir has stopped by unexpectedly. He won’t stay long, as he expects Dominic wants to get his home fires burning. Dominic laughs but is then briefly confused again, thinking he ought to have come up with the line himself. Dominic offers Sir a drink, which he accepts, provided that it’s gin and tonic and not ginger beer. Indeed, he is visiting because June called to tell him that Dominic has developed a taste for ginger beer. Sir loathes ginger beer drinkers; in fact, Cooper from Accounts was a ginger beer drinker. Dominic vows never to touch ginger beer or wish for a change again, and Sir, June, and Kevin are all relieved.

Dominic arrives at home once more, and everything goes as usual except that Kevin brings him his drink. When Dominic wonders why, June reminds him that it is their wedding anniversary. He panics, and she worries that he’s forgotten again, “like last year, when I went back to Mother’s and you had to win me back in a two-part episode.” Dominic has forgotten, but he manages to cover, transforming the wine-tasting party Sir is holding there that evening into an anniversary party. June leaves to change, and Dominic asks Kevin if any of the evening’s events seem terribly familiar. Kevin convinces him that all is well and that he shouldn’t question things, and directs him to send Kevin out to get an anniversary present. Before he leaves, Kevin spills defective perfume all over Dominic’s trousers.

Sir shows up for the party, and while he and Dominic are talking Dominic notices the laugh track that has been accompanying their comments. He orders Sir to vary one of his stock comic statements, and deduces that it isn’t the meaning of their words but the inflection that causes the laughter. Deciding that the technology providing the laughter must be hidden by hypnotic suggestion, he locates it by looking through the corner of his eye and begins disassembling the machine. While working, he points out to Sir that they have no idea what their company does. Ignoring complaints from Sir and a returned June, he manages to deactivate the machine. Once it is broken, Sir and June recognize it as a CannedLaughterTron, leading Dominic to decide that “the logic changes as we go along.” June or Sir must be an alien using mind control on him, but he remembers now that he fights evil for a living. They both deny his lunatic suggestions.

Kevin joins them, and Dominic says that he must be the alien. Kevin denies it, and then notices that the laughter is gone. He is confused but soldiers on, even when Dominic refuses to continue the charade and Kevin must play his father’s part as well as his own. They conclude the anniversary scenario as Dominic recalls that he used to travel in time and space, which June denies: “the furthest we’ve ever been is to Paris, in that feature-length Christmas special.” Dominic wonders if he’s going mad. The theme tune plays, and Dominic realizes that the scenario reverts endlessly. June has forgotten about the CannedLaughterTron, and ignores his suggestions that something is amiss. No matter what has happened, she will love him forever. Dominic continues to wonder about his mental health; even if he is mad, he doesn’t want to be sane again. He can’t remember ever loving June. They never make love, and when they kiss it’s only through the air from six feet away.

Kevin comes in. In case they are real, Dominic apologizes to them for abandoning his family in favor of his new memories. He wants a divorce. When Kevin complains that Dominic’s bizarre behavior has left June crying all day, Dominic claims that she and the rest of her world don’t even exist when he’s not around. He demonstrates that there’s nothing outside the front door, just a white void. Kevin panics and runs to find his mother. The doorbell rings, and this time the street is there, along with Sir, because they have a dramatic purpose. Dominic suggests to Sir that their company ought to manufacture machines that travel through time and space, dimensionally transcendent machine in the shape of a small blue box. Sir gives him another promotion, at which point Dominic has had so many that he is now Sir’s superior, and orders him to work on a prototype time-and-space machine.

June and Kevin return, and June announces that she has a surprise for Dominic. Kevin transforms himself into an alien monster, and June tells Dominic that he’d better save them from the monster. There’s a weapon in his briefcase that should work. He finds a Technobabble Burbulator gun, but refuses to use it on Kevin. June protests that she thought this was what Dominic wanted, then takes the gun and destroys Kevin herself. She asks Dominic why he can’t be satisfied with what she has offered him. He begs her just to talk to him, and she agrees, sending Sir away.