Peter and the Sword of Mercy is a children's novel that was published by Hyperion Books, a subsidiary of Disney, in 2009.

Written by Dave Barry and Ridley Pearson, the book is an unauthorized reimagining of characters and situations from Peter Pan, or the Boy Who Wouldn't Grow Up by J. M. Barrie, and tells the story of an orphan named Peter.

It is a sequel and fourth installment to Barry and Pearson's "Starcatchers" series, best-sellers released in 2004–2007, which was originally said at the time to be a trilogy.

Her mother Louise has been deceased for a while and her father Leonard is very ill. One evening, she is visited by one of the original Lost Boys: James, who now works for Scotland Yard.

He informs Molly about his suspicions with Baron von Schatten, an advisor to Prince Albert Edward.

James tells her he will come back the next night, giving her some time to think the whole thing over, as he has nowhere else to turn.

Meanwhile, on Mollusk Island, four men known as McPherson, O'Neal, Kelly and DeWulf wash up on shore in a boat.

Anxious to find out what is going on, Molly goes to the Scotland Yard, only to be told by his employer, Blake, that he is on vacation.

Meanwhile, a hideous man-like monster named The Skeleton, one of the "Others" that can cause pain with but a mere touch, looks for the missing tip of the sword Curtana - a.k.a.

To keep his children safe, George sends them to stay in Cambridgeshire with Neville Plonk-Fenster, an inventor and their uncle.

Wendy finally finds Peter on Mollusk Island with the help of some porpoises leading her through the ocean one at a time in the right direction.

In order to return Wendy to England, Fighting Prawn devises a plan to help Captain Hook resurrect the sunken flying ship from the previous novel (which no longer flies) so Hook can use it to return to piracy and deliver Wendy to England.

After the ship is pulled from the sea Fighting Prawn threatens Hook that if he does not bring Wendy to England, he will hunt him down, bring him back to the Island, and feed him to the Islands giant crocodile named Mister Grin.

At Fighting Prawns' request, Hook agrees to bring the four shipwrecked men with him in order to get them off the island.

Unknown to Hook, Peter stows away on the ship by hiding in its rolled up sails so he can also arrive in London to help Wendy.

Peter and Wendy are taken back to London once they are discovered as stowaways aboard the steam ship.

Upon arriving in London, Wendy, Peter and Tinker Bell escape the police with the help of some rats (whom Tinker Bell can speak to), and from there travel to Lord Asters' house where, after avoiding bobbies watching the house, meet up with John, Michael, Neville, Mrs. Bumbrake, and Lord Aster.

After defeating Lord Ombra and the "Others", Molly returns home with Wendy, where they are reunited with George, John, and Michael.

Wendy also has come to enjoy telling her brother about Peter Pan by the end of the story.

While Peter is in London, Fighting Prawn deals with Captain Narezza and his men when they attempt to steal the Islands starstuff.

Captain Nerezza: An agent of the Others who posed a threat to Peter in the second book and is attacking Neverland through the use of spies.

Cheeky O'Neal, Rufus Kelly, Frederick DeWulf, and Angus McPherson: Four castaways who arrive in Neverland and turns out to be spies sent by Nerezza.