Attack of the Jack!

Attack of the Jack is the second book in the Goosebumps SlappyWorld book series.

The cover shows Captain Jack the Knife, with many gold coins in the air.

Synopsis
Violet Packer and her brother Shawn are visiting their Uncle Jim for the summer. He lives in an old house by the seashore. Jim was a sailor and he has collected strange and fascinating items from the sea. While exploring a back room, Violet and Shawn discover a locked trunk, which is a pirate's chest. The trunk is wrapped in old, heavy chains and is also locked with a huge rusted lock. But Violet and Shawn managed to get it open.

They lift the lid slowly and see that's filled with antique jack-in-the-boxes. One box is hidden under the others, covered in dust and it plays an odd, unpleasant song. Then up pops a mean-looking puppet, an old pirate with a dirty red bandanna over his long greasy hair, scars on his cheeks, a beard and one eye missing. Then he bounces on his spring, rasping "Thanks for letting Jack the Knife out!". Violet and Shawn now face new and troubling questions: Will Jack return them to their uncle? Just how much is a pirate's promise worth?

Plot
Violet and Shawn Packer arrive at Sea Urchin Cove, and they eat out at a restaurant called ''The Whistling Clam. ''When Violet tells the waitress they were staying with their Uncle Jim Finnegan, the waitress tells them not to go there and go back home.

They arrive at their uncle's house, where they see a black cat, but the cat starts talking. She was calling Admiral Jim. Jim appeared, and gave them a hug. At dinner he tells the story of how his cat, Celeste, is able to talk.

There was a man named Danny Lubbins, whose his ship sank. He was stranded at sea with the black cat for 300 days, and to keep himself from going mad, he taught the cat how to talk. They spotted land, but only Celeste made it, and Danny died.

Before Violet and Shawn go to bed, they explore their uncles knickknacks and fake treasures, including one that was used on a movie set, but was left there, but then, Jim told Violet and Shawn to stay away from the forbidden room.

Slappy the Dummy interrupts the story, and asks the reader if they think the story is starting to get scary.

The next morning, after their lobster omelet breakfast, Jim leaves the house, and while gone, Violet and Shawn sneak into the forbidden room. They find a chest full of jack-in-the-boxes, each one played ''Pop! Goes the Weasel!'' As they turned each crank, Celeste came in, and told the children she was going to tell Admiral Jim on them. But since they were in trouble anyway, they opened the last one, but it wasn't playing the song the others were, it sounded eerie, like horror movie music, then a loud deafening explosion occurred.

Out popped Captain Jack the Knife and his crew, a female pirate named Mad Madeline, a chimpanzee named Chuckles, and a two headed pirate named Salty and Pepper Magee. The kids discover that their uncle has turned into a jack-in-the-box. The jack-in-the-boxes all step out of their boxes and grow life size. The kids flee, but the pirates catch up. Jack tells Violet and Shawn his canary named Captain Pip was trapped on Clam island, and tells them he wants Violet, Shawn, and his crew to get the bird back. If they get the bird back, they would go back in their boxes and Jim would turn human again. As they got on the ship, The Jolly Sea Scab, Celeste whispers to Violet not to go that ship.

Slappy interrupts again to brag about Celeste.

The ship ride to clam island is a nightmare. Salty and Pepper keep arguing with each other, Madeline keeps making bad jokes, and Chuckles is stirring the ship. Then all the sudden, the ship starts sinking, and they lose their map. Chuckles takes the only life boat, and Violet and Shawn plummet into the icy cold ocean.

As hope seems lost, Madeline, Salty and Pepper had a raft the whole time. They get on board, and Madeline attempts to shoot a flame pistol in the sky, but the pistol is wet. Luckily, another pirate ship comes, and it almost crashes them.

Slappy interrupts again, and says he hates it when ships do that.

This ship belongs to a pirate named Captain Billy Bottoms. They are glad that they were rescued, but then it turns out that Billy rescued them so he can have them as slaves, working on the nearest island, picking bananas. While there, Madeline gives a signal, and Violet and Shawn run for it, but they land in a banana cart filled with tarantulas. They get out and see two girls about Violet's age. They tell Violet and Shawn they were on Clam Island.

Violet and Shawn then find the canary. They and the two pirates sneak on Billy Bottom's ship, who isn't there because he was still on the island looking for his prisoners. They escape the island with Captain Pip.

When they arrive home, they give the canary to Jack the Knife, but he says it was the wrong bird. But he accepts it. But then, he tells Violet and Shawn that he was not going to bring Jim back. He was going to leave him a toy forever. Violet says, "But you promised!" Jack then says he gave a Pirates Promise, which is worth nothing.

As the pirates surround Violet and Shawn, the Ghost of Danny Lubbins comes in the room. Jack the Knife begins shaking in fear. He says he is afraid of ghosts, so Jack and his pirates shrink to toy size and go back in their boxes, turning Jim into a human again. The ghost of Danny Lubbins takes Celeste, and thanks the children, then vanishes with the cat. When Jim wakes up, he talks to Violet and Shawn like the whole thing never happened, though it certainly did.

Slappy concludes the story, jokes about Jim, talks about how him and Jack the Knife have much in common, and wraps up the story.

Audiobook
Attack of the Jack received an audiobook adaptation on July 1, 2017.

Trivia

 * The working title for this story was "Jack Attack".
 * This title sounds similar to Attack of the Jack-O'-Lanterns.
 * In one scene, Uncle Jim drank something that he claimed was Diet Sprite. Violet said that the liquid didn't look like Sprite because it was brown.
 * In the book, Jack the Knife's hook was on his left hand, but on the cover, it's on his right hand.
 * Jack the Knife's appearance on the cover looks nearly identical to the appearance of a character that appeared on the cover of the book Pirates of the Sea!. Both books were illustrated by Brandon Dorman.
 * This book references Diet Sprite, Pirates of the Caribbean, Johnny Depp, and the movie Jaws.