|This needs a stretch.|
The mansion was the home of Mr. Carswell.
Insert details here.
Scooby-Doo, Where Are You!
When the gang found a bank guard out in the middle in the road in a half conscience state, they took him to his boss's house after finding the address of the latter's in the wreckage. Once there, he was laid out on the couch with a blanket over him and Mr. Carswell said he would take care of him. In reality, he took him down to the basement because the bank guard had incriminating evidence against him of him stealing from his own bank. He made it look like the guard had been in a car accident from a falling tree, but he had really set up a trap for the guard (as the Creeper) so he could ransack the guard and the inside of his car to find the evidence against him.
By the time they caught Mr. Carswell as the Creeper, the sheriff had freed the guard.