Violet and Shawn Packer released him from his jack-in-the-box, when he is released, he grew life size, and turned their uncle Jim into a jack-in-the-box, he then makes a deal with the kids, go to Clam Island with his crew, to get his canary Captain Pip back, and in return, he'll turn their Uncle Jim human again.
When the kids come back, Jack tells them they brought back the wrong canary, but he accepted it, he then told Violet that his deal was a Pirate's promise, and those are worthless, so he won't bring Jim back.
As he and his Pirates surround the kids, the ghost of Danny Lubbins came, Jack is afraid of ghosts, so he and his pirates shrink and go back in their boxes.
He wears a red bandanna over his black hair. A bright blue jacket over a black and white stripped shirt. He has large brown eyes and a long nose above a black mustache. He carries a long bladed knife in his right hand, and his left hand is missing, just a long curled hook were his hand should be.
He is rude, a liar, and ruthless, he can be quite fearsome too. However, he is afraid of ghosts. When he see's one, he surrenders.
- His hook is on his right hand on the cover. In the book, the hook is on his left, though.