Someone has stolen the diamond from Muhammed Karat's gold shop. Five stones have disappeared in a very short time. Muhammed Karat suspects tht the one who of his own employees - Margaret Rose, Tommy Bolt or Larry Smith. The police in the small town of Valleby cant find the thief
On christmas eve, the gravenstein family stays for a few weeks in Valleby Hotel. They have a very valuable Japanese Apple Hound. The hotel personnel prepares a big traditional christmas celebration, but soon the problems begin. The dog has disappeared. billy and maya again has tricky case to solve.