The date is 8 June 2004 and Ian Chesterton has had to wait 244 years to see a transit of Venus, having missed it by a matter of months the first time round. He’s especially keen to see it this time because in a strange sort of way, he owes the transit his life. A transit is a bit like a solar eclipse, when one heavenly body moves across the disc of another - in this case when the planet Venus crosses the path of the Sun. In 1769 an expedition was sent out to observe the transit to help the early astronomers create a map of the skies and Ian’s story takes place aboard that ship.

At the time, he and a fellow teacher Barbara Wright were travelling with the Doctor and his grand-daughter Susan aboard the TARDIS. They’d already shared a number of adventures together and had recently encountered a race called the Sensorites, during which time Susan discovered she had a talent for telepathy. She was told this empathy wouldn’t persist outside the ultra-high frequencies of the Sense-Sphere, but Ian was sure a few remnants were still in evidence after they left. Unfortunately, the Doctor had taken umbrage at some of Ian’s innocent comments and had vowed to abandon him and Barbara at the ship’s next landing place. Not long after, the Doctor announced that they’d arrived on Earth and he opened the doors before anyone could say goodbye or have a chance to collect their thoughts.

The TARDIS doors shut behind Ian and Barbara and they found themselves on the deck of an old fashioned sailing ship. Rain lashed down on them and the ship lurched from side to side in the wind. They turned to see a horde of sailors gazing at them with a mix of fear and anger on their faces. One of the sailors accused them of being demons, but the fact that Barbara was a woman seemed to bother them even more. They accused her of bringing a curse upon them and moved to throw her overboard. Ian knew there was no point trying to argue with these people’s primitive superstitions, so instead he tried to protect Barbara as they both backed away towards the TARDIS. Then suddenly everything went black…

…Ian woke up and saw a middle-aged man wearing a powdered wig staring down at him. The man asked him where he came from and in his semi-delirious state, Ian mentioned recently seeing the metal seas of Venus. The man was shocked and asked Ian if he‘d been sent to observe them during the transit, and although the words made little sense to Ian, he readily agreed.

Although there was a huge bump on the side of his head, Ian was soon feeling better and was invited to meet the Captain. Ian was surprised when the man greeted him as an honoured celestial visitor, but then he remembered their earlier conversation in which he inadvertently claimed to have come from Venus. The Captain explained that during the storm, the mast of the ship had come loose and hit Ian with some force. Ian asked about Barbara, but the Captain denied seeing any women and said Ian had come aboard with only one other companion - the Doctor.

As soon as Ian was able to speak to the Doctor alone, he learned that Susan had refused to leave until they’d seen Ian and Barbara safely on their way. Watching on the scanner, they saw the sailors attack and the Doctor had reluctantly agreed to go out and rescue them. Confronted by the angry seamen, the last thing the Doctor recalled seeing before he too lost consciousness, was the TARDIS being heaved over the side of the ship. He believed that Barbara must have already made her way inside the TARDIS, but he couldn’t be certain and Ian was worried she’d drowned. The Doctor was more concerned about Susan, because if Barbara was indeed dead then his grand-daughter was condemned to live out her life alone, trapped at the bottom of the Pacific Ocean. Ian was determined to recover the TARDIS so he suggested they leave this ship as soon as it next arrived at land, assess the available technology, build whatever they needed and then come back. The Doctor pointed out that they were in the year 1770 and their host was none other than Captain James Cook. The ship they were on was the Endeavour, which had recently left Tahiti after observing the transit of Venus, and they were now on their way to discover Australia…

They were lucky not to have been executed as stowaways, but fortunately the superstitious people of this time had believed Ian’s claim to have come from Venus and were willing to treat them as honoured guests. Despite everything, the Doctor was overjoyed to get the chance to spend time with the famous navigator Captain Cook. Cook requested that Ian work alongside his young chief scientist, Joseph Banks. Ian was familiar with Banks’s reputation as a naturalist who’d discovered many new species, but he found the man to be obsessed with his work. He thought nothing about killing an extremely rare creature simply so he could have a specimen to sketch or to display in his collection. Of course, at this time no one knew about the dangers of species becoming extinct, but Ian suspected Banks wouldn’t have cared even if he had known. Ian quite liked the man and certainly admired his single-mindedness and passion, but it wasn’t long before he had reason to be suspicious, and even fearful, of the young scientist.

The sea was very calm the next day and Ian and Banks were delighted to see an albatross flying in the sky above them. Ian commented that he’d heard many people believe albatrosses contained the spirits of people who’d drowned at sea and that to kill one would bring a dreadful curse upon the perpetrator. Banks dismissed this as superstition and went below deck to collect something. As soon as he was alone, Ian thought he could hear a faint woman’s voice calling him by name. Banks returned with a crossbow and then, without warning, he fired a shot into the sky. As the dead albatross fell to their feet, Ian accused Banks of being reckless as the other sailors might end up believing their voyage was cursed. Banks then appeared to go into a trance and started quoting poetry, but when Ian challenged him, he returned to normal. Ian made an excuse to leave and went to find the Doctor.

Ian tried to warn the Doctor that Banks wasn’t what he seemed and that he might even be an alien or a time traveller, but the Doctor refused to listen to such nonsense. Ian explained that Banks had just quoted to him a section from “The Rhyme of the Ancient Mariner” - which hadn’t been written yet and the author, Samuel Taylor Coleridge wouldn’t even be born for another two years - but the Doctor simply put this down to the blow Ian had received to his head earlier. He assured Ian that Banks would shortly become a famous man, so it was likely that at some time in the future he would tell the writer about this incident. Ian thought this sounded plausible so he resolved to forget about what had happened.

Ian thought Cook to be a good captain who earned the loyalty of his crew. His enthusiasm kept them going, even through the worst weather. Ian was keen to reach land, but he couldn’t remember the date when the Endeavour was due to reach Australia. He learned that the crew was split into those who believed they were approaching a continent and those who believed it would just be a collection of islands. Ian had to hold his tongue to make sure he didn’t undermine the discovery that awaited them. He remembered a young student back at Coal Hill School who’d shown a great deal of promise, so Ian had encouraged him to discover things for himself. Unfortunately, just as his experiments were about to bear fruit, another student spoiled things by revealing the answers that he’d got out of an encyclopaedia. As a result of losing that moment of discovery at such an impressionable young age, Ian’s star pupil lost all interest in science.

Sometime later, Ian found Banks updating his journal and he watched from a safe distance, knowing this was history in the making. But as Banks scribbled his notes, Ian was shocked to discover he was making references to the territories of Australasia, even though they had yet to be discovered, let alone named. He went on to make notes about the future charting of the area and then details of Captain Cook’s nephew Isaac, who in the future would be the first Englishman to step foot on the east coast of Australia. Ian stepped from the shadows and accused Banks of writing about things that hadn‘t happened yet, but Banks claimed not to know what he was talking about and even suggested it was Ian who was the one making claims about the future. Banks laughed it off and Ian stormed back to his cabin in frustration.

Ian now knew they would reach land in less than two months’ time. It was a long time to wait and he knew they’d still be no nearer finding the equipment they needed to retrieve the TARDIS. Ian told the Doctor what he’d heard Banks say, but although the Doctor suggested the man may have simply been fantasising about the future, they both knew this was a weak argument. Ian continued worrying about Banks for the next few days, but he was eventually distracted when the weather conditions made their voyage hazardous. Captain Cook was anxious for them to find a place to shelter from the storm where they could take on supplies and conduct repairs on the ship, but although they soon reached land, the bays all turned out to be inhospitable. Banks became frustrated as he could see many interesting features on the shoreline as they sailed along, but they were unable to stop.

Eventually the Endeavour reached a bay which seemed to offer everything as it was calm and sheltered and the entrance was several miles across. It had one particularly unusual feature - a row of rocky peaks that resembled a man’s hand, and Cook named the area Point Five Fingers. Everyone was desperate to land, but they couldn’t reach it before nightfall and by the time daylight returned, the bay was far behind them. Banks insisted that the ship turn back, but the strong winds made it impossible. Ian rebuked him for wanting to risk everyone’s lives just in case he was missing the chance of discovering a new shrub, but Banks felt that gaining knowledge was more important. Ian was reminded of the time on Skaro when the Doctor’s curiosity almost led them all to their deaths. Comparing the two incidents made Ian realise that neither the Doctor nor Banks were wicked or careless men, but then something happened to make Ian change his opinion…

As Ian hit the water, he thought his heart would stop from the impact and the terrible cold. His anger towards Banks helped him to focus his mind, and he knew that no one else aboard the ship would be safe unless he could warn them about Banks‘s true nature. Just then, he saw a rope being thrown towards him and he managed to tie it around his waist, whereupon he was slowly pulled back aboard. Then, to his surprise, Ian discovered he owed his rescue to none other than Banks himself, who’d called for help from the other crewmen. Before Ian could protest further, he slipped into unconsciousness.

For a while Ian was gripped by a fever that made him delirious. He suffered terrible nightmares of Barbara‘s body at the bottom of the ocean, slowly turning into coral, and then her soul rising from the waters and transforming into an albatross, only to be shot down by Banks‘s crossbow. Ian hated Banks more for giving him those dreams than he did for trying to kill him. The Doctor looked after Ian and made sure his recovery was swift, but by then it was April and the Endeavour had started out on its return voyage to England. Captain Cook had wanted to travel by way of Cape Horn, but was concerned that the ship might not survive the conditions of that route, so instead they were going via the east coast of New Holland…an area now known as Australia.

Banks visited Ian in his cabin and received a frosty reception. The botanist appeared genuinely surprised by Ian’s reaction and wondered whether he blamed him in some way for his fall from the deck. Banks assured Ian he did everything he could to save his life, but then Ian accused him outright of pushing him overboard and trying to kill him. Banks told Ian he respected him as a fellow scientist and colleague and offered to show him something he discovered on Steven’s Island where they’d anchored briefly while Ian was recovering. He’d been hoping to discover some new species of plant, but only found one new specimen. He showed him the plant and said that because it resembled an old man’s beard he’d decided to call it Barberer after the word ‘barber’, which is latin for beard. He claims the name just came into his head, but Ian was furious and believed Banks was trying to play with his mind. He then accused Banks of killing Barbara and ordered the man to leave, but Banks turned to him and told him he would never leave him alone and would always be with him.

The Doctor told Ian they’d seen birds circling above them this morning, which was a sign they were approaching land. Ian joined the others on deck and found the weather was still inclement. Although he and the Doctor had been on board for over a month now, he’d had little opportunity to speak one-to-one to Captain Cook and he was still in awe of the man. Cook knew there’d been friction between Ian and Banks, so he told Ian that although Banks was an obstinate and stubborn man, no one more dedicated to the cause of science. He believed that if Ian and Banks were prepared to work together, they could achieve great things. Ian didn’t know whether Banks was an alien and whether he’d been replaced by a doppleganger, but he was certain the man they were travelling with was up to no good. It occurred to him that Banks may even be trying to alter the course of history and he wondered whether he should intervene. Ian asked Cook how well he really knew Banks and questioned the captain’s loyalty to the botanist, but this angered Cook. He told Ian he would excuse him this time, but warned that any such words in the future might lead to a charge to mutiny. Ian was shaken by this and realised he must be more careful not to alienate Cook further.

Ian returned below deck and found the Doctor alone with a tear in his eye, and for the first time he realised how much the Doctor had been grieving the loss of his grand-daughter. They sat in silence together. The next morning, the ship’s second lieutenant Zachary Hicks spotted land ahead and the captain honoured the moment by naming the land’s southernmost point after him. The crew believed the land they were seeing was part of New Holland, and although the Doctor and Ian realised it was a separate island, they knew it wasn’t their place to correct them.

The ship sailed on and Ian waited patiently for Banks to make his next move, confident the man would have to act before anyone actually set foot on Australian soil. As the weather started to calm and the temperature rose, they eventually arrived at their destination. Everyone aboard knew they were making history, but none of them guessed it was a moment that would still be taught to school children two hundred years in their future. However, the crew made several failed attempts to anchor and even Captain Cook’s attempt to reach land by rowboat was unsuccessful.

On April 28, they reached a more hospitable area which Cook named Stingray Bay, where they could see natives going about their business on the shore. Cook and Banks prepared to go ashore first, but as Banks passed Ian on the deck, Ian overheard him humming a tune to himself. To his horror, Ian recognised it as the tune to the song “Botany Bay”. He realised this part of the coast would eventually be re-named Botany Bay - but Banks couldn’t possibly know that, nor could he know the words to a song that hadn’t been written yet. He challenged Banks to explain where he got the name from, but Banks insisted Ian was making no sense. Ian recalled that the song was about convicts coming to Australia and he became hysterical, suspecting Banks of planning to murder everyone. He even recalled Banks mentioning the fact that he was looking for poisonous plants and he became convinced the botanist was planning to kill off the crew one by one. Banks accused Ian of being mad and the two men began to struggle…

It took three sailors to drag Ian away from Banks. When he was locked in the hold he realised he was about to miss the historic moment when the crew first set foot on Australian land. He slept for a while and was eventually woken by the arrival of the Doctor, who rebuked him for nearly getting them thrown off the ship. Ian explained what had happened, but once again the Doctor dismissed his argument and pointed out that it would be none other than Banks himself who would later recommend to the Government that criminals be transported to Botany Bay. He believed Ian’s earlier rant was most likely what planted the idea in Banks’ head in the first place, which meant Ian had inadvertently meddled with history.

The Doctor persuaded Cook than Ian was unfamiliar with the ways of Earth, so the Captain agreed he could be placed in a cabin under house arrest. Sometime later, the Doctor returned with news that one of the seaman had died from consumption, but Ian was convinced he was merely the first victim of Banks’s poison. Then later, during the night, one of the crew had his ears cut off, reportedly during a drunken fight, but Ian believed the man must have overheard something suspicious and Banks did it to stop him hearing anything again. Ian came to believe he was the lone sane voice in a wilderness of madness and he became desperate to convince everyone that their lives were in danger. He fell into a dazed stupor and as the weeks passed, Ian started preparing himself for the moment when Banks would strike.

On June 11, Ian listened as the crew took to their bunks for the night. Suddenly the whole ship listed alarmingly to one side. He banged on the door to be released, but the noise and commotion from outside was so loud, no one heard him. He could hear great splashes as the crew started throwing things into the sea. Ian was convinced Banks had managed to run the ship aground and the sailors must be trying to lighten the load to stop them from sinking. He knew the situation was desperate as the Endeavour could be smashed to pieces on the rocks. He saw a flood of water coming through the gap under his cabin door, so he tried to kick his way out, but the door was too strong. The water had risen to waist level when the door eventually opened and Ian found himself confronted by Banks. The botanist was in another trance and he told Ian over and over again that he was going to act as his navigator and lead him back. Ian recognised the words and remembered saying them himself when they were on the Sense-Sphere. He‘d been confronting a man driven mad by telepathy and had used those words to describe Barbara. Over the last few weeks Ian had come to realise how much he relied on Barbara’s calm guidance and he now knew he needed her help again, to lead him back to the person he used to be.

Ian followed Banks up to the deck where hordes of panic-stricken sailors were running to and fro. Banks handed him a spy-glass and he was shocked and amazed to see Barbara standing on the shore, waving to him. Ian later discovered the Endeavour had become stuck on the Great Barrier Reef, and although the ship was saved, it was days before he could make it to shore. Nevertheless, a great weight had been lifted from his heart and he felt like a completely different person. He and the Doctor were overjoyed to be reunited with Barbara and Susan, especially when they saw the TARDIS perched safely on a nearby sandy ridge. They sat on the beach and exchanged stories. It turned out Barbara had made it back to the TARDIS after all, but the sailors had seen her enter the box, so they lifted it and pitched it into the sea. The ship floated, but with the doors facing upwards and wide open to the elements. Susan had tied a rope to the doors and swum over to the Endeavour where she attached the other end. She returned to the TARDIS, which had started to sink, with seawater rapidly filling the control room. They shut the doors and then spent the next two months inside, mopping up all the water and making their ship presentable again.

Barbara had filled Susan in on the history and geography of the area, but most of the time they just sat there thinking of the Doctor and Ian. Susan managed to tune the scanner into the Endeavour and they witnessed the moments when Banks shot down the albatross and then pushed Ian into the sea. Barbara was convinced Banks was a villain and spent weeks hating him and worrying about Ian. When the TARDIS got caught up on the reef, they swam out to shore and persuaded some of the aborigines to help them bring the ship to shore. When they saw the Endeavour caught on the reef too, Barbara remembered Ian calling her a navigator back on the Sense-Sphere and she repeated the words out loud, willing him to realise they were nearby. The truth dawned on Ian and he asked he asked her about “The Rhyme of the Ancient Mariner” and the song “Botany Bay“. She admitted telling Susan about those too and it now became clear what had happened. Susan had evidently retained a measure of the telepathic powers she’d discovered on the Sense-Sphere and was unknowingly transmitting Barbara‘s words into the mind of Joseph Banks. She’d also passed on Barbara’s fears and feelings of panic into Ian, which had caused him to distrust Banks and attach a sinister meaning to perfectly benign events.

Ian felt desperately sorry for Banks after accusing him of all those things. Although the Doctor assured him no harm had been done and suggested they leave, Ian had one last thing to do first. He sought out Banks, but the botanist was understandably wary of speaking to him in case he was going to make further accusations, so instead he directed Ian’s attention to a new species he’d encountered. Ian was amused to discover that Banks thought kangaroos had two heads, one big one and one small one emerging from its stomach. Ian explained that he and the Doctor were leaving now - most likely going back to Venus - and he apologised for everything he’d said. Prompted by Banks, Ian claimed that everything he’s said was actually part of a deliberate scientific experiment to observe human behaviour and that he didn’t really mean any of it. In fact, he told Banks he believed him to be a fine man and a good scientist. Banks was pleased to have helped the cause of Venusian science and he readily agreed not to mention any of this when he got home. They said goodbye and wished each other a safe voyage home.