Spy Class at Christmas

Klara, Janek, Vilda and the rest of the year four pupils can't wait for Christmas – it's just around the corner! They have a Christmas market at school, and they want to use the money they make to go on a Christmas trip to a haunted castle. But the peaceful pre-Christmas season is disrupted not only by a new classmate but also by a real mystery that will have them scratching their heads. Will the class of spies manage to crack this mystery too?