Perry Mason S08 E23 The Case of the Murderous Mermaid

"Almost anyone is capable of a crime under certain circumstances."

Former swimming champion Victoria Dawn is now overweight, out of shape, and the owner of a chain of failing health spas. Desperate to regain some of her former glory she hires young actress Regina "Reggie" Lambert to impersonate her in a swim across the Catalina Channel to Los Angeles.