Mystery Train

Mystery Train Island is an upcoming island on Poptropica.

Plot synopsis
Mystery Train Island takes place during the 1893 Chicago World's Fair. Here is the description from Poptropica: How do you solve a mystery when everyone is a suspect? It's 1893, and some of the world's brightest minds are traveling by train to the World's Fair in Chicago. But after a dastardly crime puts the fate of the Fair in peril, only you can piece together the clues and collar the criminal. All aboard for a whodunit that will keep you guessing until the last twist of the tracks!

Triva

 * As of 30 July 2011, it is unknown of what the crime is (as seen in the description)