One day Memento Mori realises that he is a character in a book who has the power to travel from one book to another. He decides to strike against evil writers who sentence their characters to death. He persuades Romeo and Juliet that suicide is not the best solution and that when they are adults they will remember these days with laughter. To save many others from an untimely death he travels to the Reichenbach Falls to push Professor Moriarty to his death.

Memento Mori's efforts to save more characters from their authors is interrupted when he learns that his author plans to kill off a character. He has no information about who the intended victim is, so with the help of H. G. Wells' time-machine he takes all the characters to a different dimension where they have a better chance of survival.