While investigating the house again the Hardy boys are taken hostage by a crazy old man named Amos and another man who looks almost exactly like Mr. Dalrymple. Surprisingly they are rescued by Mr. Applegate and a bomb, which was attached to the ticking grandfather clock, is safely disarmed. Mr. Dalrymple arrives with the police and Amos falls to his death while trying to escape. The Hardy boys examine the device he was using and solve the mystery of how he managed to deliver the death threats to the secret room, as well as locating the stamps which Mr. Dalrymple's doppelgänger had stolen from Mr. Applegate.