In the "The Three ??? Advent Calendar," friends Justus, Peter, and Bob must solve an action-packed criminal case during the pre-Christmas season. Children aged 8 and up join the boys on their quest for the perfect Christmas gifts. Suddenly, events take a wild turn, and several strange coincidences pile up. What's going on here? Together with their heroes, the children open a door each day that contains a riddle, another clue, and a great detective gimmick to assist them in their search. Fully equipped, they get closer to the solution day by day. The three ??? must hurry – they have only 24 days left until Christmas.