Twins Pearl and Patrick are no ordinary twelve-year-olds. They're geniuses, hiding in plain sight, who pull heists all over the world to further their scientific and historical research. Their criminal activity, including grand theft auto and espionage, has made them a regular nuisance to both the CIA and MI5. But it's all been worth it. They've finally achieved their greatest triumph: time travel. Pearl's Chrono-Loop can take the twins anywhere in time! Their first stop: ancient Egypt, where they even get to see King Tut! But when they return home, they're arrested by TIME--The Interdimensional Misconduct Enquiry--a secret organization charged with maintaining the timeline. Turns out Pearl and Patrick didn't invent time travel, after all--that happened two hundred years ago! And what Pearl did in ancient Egypt--killing a mosquito--could have rewritten history as we know it if not for TIME agents stepping in. Punishment for disrupting the timeline is 100 years in the Eternal Abyss. But TIME, impressed by the pair, offers them a chance to become agents. Unfortunately, they fail their entrance exam and instead are banned from ever attempting time travel again. Pearl is furious, and when she's offered another chance at time travel by a rival organization, she takes it! Too late, she realizes she's been tricked and unwittingly plays a part in replacing the timeline they know with a nightmarish scenario. Now Pearl and Patrick must clean up the mess they've made. But to restore the timeline, they have to go back to the beginning--to Lion Rock--to convince the real inventor of time travel to help them save time and the world.