Perry should only vacation in places where there are no other people, because if there are only two people around one will murder the other and he'll be retained by the survivor as defense counsel.
Phil Beecher has just finished ten months in prison for vehicular manslaughter. He had one drink, the car skidded, and his passenger, the sheriff's daughter Aggie, was killed. He wants to come back to his wife, but she doesn't want him back at least in part because she was suspicious of why Aggie, an old girlfriend of Phil's, was in the car in the first place. The whole town hates him and thinks he got off easy as far as punishment goes.
It is in this environment that Aggie's sister. Charlotte, plans to steal the mill payroll and make it look like Phil did it. This will allow her to both leave the mill town behind with her married lover AND get revenge on Phil for killing her sister. But things go wrong and Charlotte ends up dead AND the payroll is missing. But, as Charlotte had planned, the entire town blames Phil and he is arrested. Enter stage left Perry Mason.
Because the case is going on outside of LA there is an entirely different cast of law enforcement characters. In fact, one complicating factor was that Perry actually came to this small logging town to do some hunting and fishing with the town sheriff, the man whose daughter was murdered.
Perry has some interesting insights here, and comes up with a pretty good psychological experiment that leads him to some crucial evidence from an uncooperative person.