Jonah, Katherine, Chip, and another boy, Alex, have no preparation before they are sent back to 1483 at the Tower of London, with the promise that they can return to the present if they can repair history. They quickly discover that Chip and Alex's true identities are the 13-year-old King Edward V and his 10-year-old brother, Richard, Duke of York. But before Chip can enjoy being the king of England, they discover that they are virtually prisoners--and that their uncle wants them dead. How can the kids repair time and return home when according to history, Chip and Alex were murdered?

Still reeling from their experiences in Roanoke in 1600, Jonah and Katherine arrive in 1611 only moments before a mutiny on Henry Hudson's ship in the icy waters of James Bay. But things are messed up: they've lost the real John Hudson, and they find what seems to be the fabled Northwest Passage--even though they are pretty sure that that route doesn't actually exist. Will this new version of history replace the real past? Is this the end of time as we know it? With more at stake than ever before, Jonah and Katherine struggle to unravel the mysteries of 1611 and the Hudson Passage...before...