Holly, Pete and Miranda are incredibly lucky! They met their favorite actor, Maurice Harty, in the park. The guys immediately decide to get his autograph, but they are alarmed by the idol’s strange behavior. Constantly looking around, he drops an envelope into the hollow of an old oak tree and quickly leaves. Friends, without thinking twice, take out the envelope and find two thousand pounds in it. The strange events do not end there. After some time, a stranger in a yellow cloak appears near the oak tree. Realizing that the hollow is empty, she quickly disappears. This must be blackmail! Young detectives decide to help their idol...