A group of brave children love solving mysteries and dark cases together with their dog, Scamper. They are the Secret Seven, one of the most popular series by the multi-award-winning Enid Blyton, loved by millions of readers around the world.

The Secret Seven are playing Indians in the small forest. Suddenly, Colin notices a strange man on the fence of the neighboring mansion. His role is revealed the same afternoon when it becomes known on the radio that Lady Lucy Thomas's pearls have been stolen. What connection could the clowns and acrobats of the circus performing in the area have with the case? It's time for Scamper to show what a clever sleuth he is!