Tegan and Turlough were sitting in the console room, Turlough listening to the sounds of banging from the interior. Then it went very quiet.
“The Doctor's all right,” Tegan told Turlough, dismissively. “He gets like this sometimes. Nothing to worry about.”
The banging started up again.
“Well, I suppose it's none of my business,” Turlough sighed.
They both turned around and jumped in surprise. A red haired girl had appeared in the center of the room and was looking around. When her eyes landed on the two, she lit up. “Tegan and Turlough, right?” she said, bounding over and shaking both of their hands. “I’m Lilith.”
“How did you get on the TARDIS?” Turlough asked.
Lilith held up her arm, showing the two companions what looked like a large technologically advanced watch. “It’s called a vortex manipulator. Not nearly as fun or as safe as the TARDIS, but it gets me from place to place.”
The Doctor burst in. “Not hat people, are you? Either of you?”
“Wear them much, I mean. I only do when I go out.” He grabbed the hat stand. “It's silly to have this thing getting in everyone's way.”
Tegan threw her hands up. “I don't believe it. There's so much to do aboard this ship and all you're worried about is tidying away the hat stand.”
“Well, I have to start somewhere.” The Doctor turned to take the stand out of the room, but came face to face with Lilith instead.
“Hello!” she chirped.
“Ah, it’s you,” he said, and stepped around her.
Lilith rolled her eyes. “Well, hi to you too, Dad.”
“Dad?” Tegan exclaimed.
Both Gallifreyans pretended not to hear her. “You know, I don’t know why you were complaining about the other desktop. I mean, just look it this one. It’s all white and bland. At least the coral one has some color.”
“You’ve never complained about this desktop before,” the Doctor sniffed.
“That’s ‘cause I’ve never seen it before,” Lilith told him. “This is my first time going this far back in your timeline.”
“Do you know this girl, Doctor?” demanded Tegan.
The Doctor nodded. “I’ve met her a few times. She thinks she’s my daughter from the future.”
“That’s because I am,” Lilith insisted. “You don’t have to believe me, not yet. But you will eventually.”
“Doctor?” Turlough interjected. “Something's happening to the controls.”
The Doctor went over to him. The monitor on the console says, ‘Boundary Error: Time Parameters Exceeded’. “Ah, we must be on the outer limits. The TARDIS has drifted too far into the future. We'll just slip into hover mode for a while.”
“Time Parameters? There’s a limit of where you can go?” Lilith questioned.
The Doctor looked at her. “Of course. Does your TARDIS not alert you when you go to far?”
“Evidently not, as she once took us to the year one hundred trillion.”
“But that’s the end of the universe! Not even the Time Lords have gone that far forward.”
“It’s not a trip I’d recommend. It was cold, dark, and filled with Futurekind and the Master.” Lilith shuddered. “Not the best place for a picnic.”
Tegan looked at the monitor on the other side of the console. “We're in the Veruna system, wherever that is.”
“Ooh, Veruna! There’s irony for you.” The Time Lady laughed.
“Veruna is where one of the last surviving groups of mankind took shelter in the great, er.” The Doctor hesitated. “Yes. Well, I suppose you've got all that to look forward to, haven't you?”
“In the great what, Doctor?” Tegan asked.
“All civilizations have their ups and downs,” the Doctor replied, vaguely.
Turlough read from the monitor. “Fleeing from the imminence of a catastrophic collision with the sun, a group of refugees from the doomed planet Earth—”
“Yes, that's enough, Turlough,” the Doctor said, firmly.
“Yes, thank you, Turlough.” Lilith grinned.
Tegan turned on the scanner to view the planet. “You mean some of the last humans are on this planet?”
“Can we land? Can we visit them?”
The Doctor shook his head. “Laws of time.”
Lilith snorted. “Since when has that ever stopped you?”
“Now, we mustn't interfere. Colony's too new, one generation at the most. The future hangs in the balance. Now, I've got another one of these somewhere. Put them side by side, we'll have a pair.” The Doctor carried his hat stand out of the console room.