The battered wreck of the colony ship was nestled in a shallow valley, with a meagre huddle of crudely-constructed buildings clustered along its flanks. Workers scurried around the settlement, busily preoccupied with restoring order to their lives.

The time of chaos on Frontios was over at last. There would be no more bombardments from the skies. At first the colonists had celebrated their good fortune, but they had now begun the task of rebuilding the colony. These survivors of the destruction of Earth were at last unhindered as they set out on what they termed the Long Path back to knowledge.

This was all thanks to the intervention of a Time Lord known as the Doctor, and his companions Tegan and Turlough. The trio were gathered beside the Doctor's TARDIS bidding farewell to the colonists.

The Gravis, a creature capable of considerable gravitational power, had been responsible for the years of meteor bombardment suffered by colonists. The Doctor had marooned the creature on the uninhabited world of Kolkokron.

‘He's exercising his animal magnetism on the rocks and boulders,’ the Doctor joked lightly.

‘It's nothing but rocks and boulders out there,’ said Tegan, suddenly very much aware of the import of her words to what were the descendants of her race. ‘All the planets are deserted, according to the TARDIS scanners.’

‘So the last of Mankind is, after all, quite alone,’ observed the colony leader, Plantagenet.

‘Alone, but in good hands, Plantagenet,’ the Doctor assured him. ‘Speaking of which, I know it's not much, but, a farewell token.’ He presented the colony leader with the TARDIS hat-stand, a souvenir of their recent experiences.

‘Frontios is honoured,’ replied Plantagenet, ‘but surely you'll stay a while longer and enjoy some of the new colony we're building?’

‘Oh, no, far too much of my own repair work to be done,’ explained the Doctor hastily, edging back towards his waiting craft. ‘And besides,’ he added, ‘time and the Time Lords don't permit it. There's an etiquette about these things which we've rather overlooked.’

‘But Doctor,’ Plantagenet's deputy, Mr Range, protested, ‘you've done so much for us!’

The Doctor coloured slightly, and visibly winced. ‘Yes, quite.’ He lingered for a moment in the TARDIS doorway. ‘Don't mention it,’ he advised the colonists and abruptly disappeared inside.

Range's daughter Norna, standing close by Turlough, shook her head in wonderment. ‘After all he's done, he just says ‘don't mention it'!’

‘He means it literally!’ Tegan smiled, and then followed the Doctor into the police box interior.

‘Don't mention it,’ Turlough advised, echoing the Doctor's words. ‘To anyone,’ he added, illustrating this with a cutting gesture of his hand. He followed Tegan into the TARDIS, closing the door behind him. Moments later, the time craft dematerialised.

Plantagenet studied the Doctor's gift thoughtfully, already formulating plans for a town square with the hat-stand as a central monument. Picking it up, he and Range walked away.

Norna made to follow them, but hesitated as she heard something jangle in her trouser pocket. She pulled out a couple of small, oddly-shaped pieces of metal, given to her much earlier by Turlough. They were coins, part of the currency on Turlough's homeworld. Each coin had a small hole drilled through the centre. Norna recalled his words: ‘It's a two corpira piece. You blow through the hole for luck.’

The colony had its hat-stand, but for Norna, the coins would serve as a reminder of her brief friendship with Turlough. She put one of the coins to her lips and blew.

‘Good luck,’ she murmured, but no one heard.

The Doctor had gone off to check on Kamelion, the shape-changing robot he'd acquired on his travels. The automaton had developed a fault soon after its arrival, and despite the Doctor's frequent tinkering, Kamelion spent most of its time in a deactivated state. ‘Now listen you two,’ the Doctor said, as he arrived back in the console room, ‘if the Time Lords ever hear about our little trip to Frontios there will be serious trouble.’

At that moment a sudden groaning sound filled the room. The Doctor frowned and put his ear to the console.

‘What would have happened if we hadn't been there, Doctor?’ Turlough inquired curiously.

‘The TARDIS engines would be working properly, for one thing,’ Tegan replied, ever critical of the Time Lord's control of his craft.

The Doctor, resorting to his cure for all technological ills, thumped the console with his fist. ‘Oh, there's nothing wrong with them,’ he replied insincerely.

‘Then why are they making that funny noise?’ Tegan wanted to know as the groaning sound increased audibly in pitch.

Turlough consulted the flight computer. ‘We're going far too fast, Doctor,’ he observed mildly.

The Doctor hurried over to see for himself.

‘Stop the engines,’ Turlough suggested, as the noise increased even more, and the console room began to shudder under stress.

The Doctor tried to appear unconcerned. ‘No, no, leave them. This will pass shortly. They're all right.’

The groaning sound was joined by a clanking noise, accompanied by a jolt which had the trio gripping the console for support.

‘What's happening?’ shouted Turlough, as the floor tilted alarmingly and his feet began to slip out from under him.

‘The Gravis?’ suggested Tegan helpfully.

‘Oh, no; this is something more powerful!’ the Doctor explained, clearly worried now. ‘We're being pulled into a time corridor. Trying to pull against...’ He frantically punched in a series of course corrections, but the TARDIS failed to respond.

‘A time corridor?’ Tegan echoed, confused. ‘Where?’

‘I don't know,’ the Doctor confessed, ‘but I think we're about to find out!’

Prologue | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | Epilogue