The Hangman’s Revolution by Eoin Colfer

F.B.I. agent Chevie Savano is trapped in a nightmare future. Unless she can return to 19th-century London and change the course of history, millions will die.

Luckily she has Riley the boy magician and a Victorian gangster with lovely hair to help her battle two crazed villains, who have brought the military technology of the future back in time – with potentially disastrous consequences.

The stakes are higher than the hangman’s noose and only Chevie can save the day. Assuming she can avoid being killed by a couple of psycho warrior-nuns first . . .