When pieces of equipment start disappearing from the new Aquamarina playground, it's up to Violet the mermaid and her best friend Wally the narwhal to solve the mystery. Back matter includes ocean science and civil engineering facts.

While visiting a friend in New York City, the Aldens investigate the theft of a valuable diamond.

Targeted by Interpol after a series of spectacular heists, a reluctant Amy and Dan are ordered by Vesper One to steal the world's largest diamond, a demand that is challenged by their efforts to rescue the Cahill hostages and stop a Vesper mole.

There is a legend that if the ravens at the Tower of London ever leave then Britain will fall, so when somebody steals the birds, the Queen calls for Mac B. to find the thief and retrieve them--a mission that takes him to Iceland, where he encounters secret submarines, hungry polar bears, and his arch-nemesis from the KGB.

When their friend Jack cannot join them, Bub the pug and his human, Bella, vow to bring him souvenirs from their road trip, and despite some bumps along the way, Bub calls their trip a big success.

Somebody has broken into Remy the Raccoon's home and stolen his most treasured possession, his grandfather's journal filled with pictures and family stories--so Remy and the Critter Crew, together with a shifty cat called Buttercup (whose motives are suspicious), set out to track down the thief, encountering many dangerous animals on the way.

In 1989 someone is threatening to steal the crown jewels, so the Queen of England summons Mac B. to England to protect them--and when they are stolen from a locked dungeon cell, where Mac and Holcroft, one of the warders, are supposed to be guarding them, it is up to Mac to figure out how they were stolen, and whether the thief is the descendant of an Irish soldier-of-fortune who tried to steal them in 1671, or someone else entirely.

Sam, a yellow Labrador puppy, is Emily's most favorite Christmas present ever, but when Sam is stolen from the backyard, Emily is determined to get her precious puppy back.

When Geronimo Stilton learns someone wants to steal the antique silver skates being offered as a prize in Mouse Island's annual winter Ice Skating Championships, he races to uncover the mysterious thief and save the prize.

Nani likes to sit outside and sew, but little things like her thimble keep disappearing. Yasmin turns detective and applies a science lesson to solve the mystery.