The year is fifteen billion and seventy-three and Theo - teenager, TimeJumper, legend - is the biggest celebrity on the Two Planets. Theo knows there's only one rule when you TimeJump: Don't Touch Anything. Just the slightest change to events could have catastrophic consequences. But Theo's been spending a lot of time with Quincy Carter One, the man in charge of TimeMaster Corporation. Quincy's starting to think that Rule 1 doesn't apply to him. Why not fiddle about with history? Meanwhile, back in the present Jules and Gen are too busy worrying about their first date to wonder what Theo's up...