The 5 sleuths consist of the siblings Betty and Pip, Harry and Daisy, and Freddie. Their group is completed by Buster, their dog. During their vacations, they all come together and solve detective cases, undaunted by anything! The time has come for the five friends to reunite once again! Their holidays are peaceful until a Siamese cat disappears, and they become the 5 sleuths again. The search for the thief of the valuable cat, which many would like to have, is not an easy task. And while they seem to be at a standstill, little Betty has a brilliant idea…