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 dissapeared. Billy and Maya again has a tricky case to solve.
Somebody is stealing diamonds from the jeweler Mohammed Carat! It looks like the culprit is someone on his staff, but who? Is it Luke Smith, the recently hired fitness fanatic with a taste for the finer things in life? It surely can’t be Vivian Leander, the loyal shop assistant who is now short of money . . . The police in the little town of Valleby are stuck, so they contact young detectives…