[Ahata Misteri]

Larry and Agatha were preparing for Christmas Eve when cousin Darren appeared on the doorstep of the Mystery House. He asks the young detectives to help investigate a case handled by their ancestor Leonard Mystery. This is how Agatha and Larry's new adventure begins. They will visit the family crypt in Highgate Cemetery, go down a tunnel to an underground river and even end up in Buckingham Palace! The hunt for evidence becomes more and more interesting with each passing hour!.

Twelve-year-old detective Agatha Mistery travels to New York to participate in the Big Hunt which brings the best detectives from all over the world to compete against each other.

"The life of the famous Mr. Kent, the butler of the Mystery House, is in danger! Underworld kingpin Morton Mystery, the lousy sheep of the family, has kidnapped him and only agrees to return him in exchange for an investigation into the 'Christmas heist'. The fact is that on the night of December 24, someone robbed the museum and . . . framed Morton himself! Agatha and Larry are forced to get down to business . . ."--Google translation of synopsis from OCLC.

Larry travels to Lisbon to investigate the murder of a ceramic artist.

"Agatha and Larry Mistery investigate the theft of a valuable diamond in the rough from an auction house. The trail leads them to Amsterdam, where they participate in a complicated investigation, aided by Grandmother Jubilee and their dog Sherlock"--OCLC.