Tom, Mirjam and Snuf are staying over on a farm, where they bump into a dangerous smuggling ring. They move to an old haunted castle, while Snuf notices something strange.

Tom is sure that he saw someone at the haunted castle, but nobody believes him. Nephew Jaap has his attention only for Mirjam and jealousy is seperating them. After a fight with Jaap, Tom goes out for research together with Snuf. Snuf follows a trail that leads him to a secret passage.

Tom and Snuf are being caught by smugglers. The leader wants to kill these unwelcome guests. Meanwhile Mirjam and Jaap are worried and feel guilty, but could they find Tom in time? Or is there any help from an unexpected side?