When diamonds from a five-year-old robbery start appearing on the black market, the insurance company hires Richard Diamond to recover the gems. His primary suspect is the man who convicted of the crime and just released from prison, but the private detective begins believe that perhaps the man is innocent of the original crime as he maintains.
Ed Murdock is a hot-headed rodeo star. When someone sabotages his equipment, he attacks who he thinks is responsible. It seems someone is out to get him but Murdock doesn't seem willing to think through the problem...he just wants to hit someone. So, Richard Diamond agrees to stick with Murdock and keep him out of trouble and possibly save his life.
Richard Diamond gets a call from his answering service that a new client is willing to pay triple his daily fee. It's a trick and Diamond is mistaken for a guy who stole a painting. Now he has to find out who set him up and why.