When thirteen-year-olds Jonah and Chip, who are both adopted, learn they were discovered on a plane that appeared out of nowhere, full of babies with no adults on board, they realize that they have uncovered a mystery involving time travel and two opposing forces, each trying to repair the fabric of time.

Jonah, Katherine, Chip, and Alex suddenly find themselves in 1483 at the Tower of London, where they discover that Chip and Alex are Prince Edward V and Richard of Shrewsbury, imprisoned by their uncle, King Richard III, but trying to repair history without knowing what is supposed to happen proves challenging. Author's note includes historical facts about the princes and king.

Time travelers Jonah and Katherine arrive in 1611 to rescue missing child John Hudson, son of the explorer Henry Hudson, but just as the mutiny on the Discovery is supposed to start, Jonah and Katherine's knowledge of history is tested once again, and they fear that more is at stake than just one boy's life. Author's note includes facts about Henry Hudson's explorations.

Told from separate viewpoints, Chess, Emma, and Finn Greystone, ages twelve, ten, and eight, investigate why their mother went missing and uncover their ties to an alternate world.

Told from separate viewpoints, as Finn, Emma, and Chess Greystone and Natalie Mayhew, ages eight to thirteen, continue their quest to rescue their mothers they must return to the alternate dimension where truth is illegal.