From The Perry Mason TV Show Book (Revised)
This is another unusual episode. It finds Perry away in Europe on business, and movie star Barry Sullivan playing his friend, lawyer Ken Kramer.

Kramer has a strange case on his hands. A woman named Lona hired him to bail out a female thief named Maxine, who had stolen a $50,000 necklace from Lona’s stepsister, Amy Reid. Amy happens to be the widow of a prominent yachtsman who drowned in the Catalina Channel four years before. Lona’s motive for freeing Maxine is to learn where she got the combination to Amy’s safe. Members of Amy’s household think Lona was in on the robbery, and so do the police after they discover Maxine shot to death in a children's playground.

Ken doesn’t agree.

Webmaster's Note: Tom Grossman notes that the character name is Lona, not Lola, and that she is the half-sister of Amy Reid, not her stepsister. Also, Maxine Nichols is played by Nina Shipman. Bettye (correct spelling) Ackerman played Amy Reid.