Blair and his counterpart discuss the case thus far about the murder of a man who changed his will, and the boat that was tampered with that caused his drowning. The obvious suspect is the brother who stood the biggest risk in losing out in the changed will. Blair suspects someone else has just as stong of a motive, and is the one who tampered with the boat.
The crime scene is recreated verbally as Blair goes into great detail. The local marshall is chomping at the bit to arrest his suspect, but Blair wants to confirm some details first. Blair has a drink with a couple of gents, but from the interchange of conversation, I’d say that Blair is just using the situation to gather fingerprints to compare with some that were found on the boat where it was tampered with.
The mystery is exposed as blair sets the sheriff out for a warrant to arrest the killer.