Perry Mason (1957)

S8E28 The Case of the Grinning Gorilla

Della acquires the diary of a woman who drowned at an auction, and as she delves into its pages, she becomes convinced that the woman's death was misclassified as a suicide. This belief propels Perry into a complex case featuring an oddball millionaire, his two conniving aides, and a gorilla with a penchant for stealing.