There is a TV crew at the school filming an episode of Inspector Derk, the kids' favorite detective show. Some students get a chance to intern on the set, including Charly & Co. Some strange thinks start happening: a camera cable is cut, someone puts sleeping pills in the director's coffee mug, etc. That's sabotage! All members of the cast and crew are suspects for Charly and the kids. Except for Stefy, who has a small crush on Derk, the actor playing the main role.