Perry Mason - Season 1 Episode 38 : The Case of the Terrified Typist 1966

While a woman is searching the office of the South African Diamond Company, George Baxter enters to meet Walter Lumis and Duane Jefferson. He notices things in disarray and questions the woman. She makes an escape, enters Perry Mason's office, and pretends to be a typist sent by a temp agency. She leaves unannounced a short time later. Meanwhile Baxter calls for the police assuming a robbery has taken place. That evening the dead body of George Baxter is seen being thrown from a pier. Duane Jefferson is identified as the person who threw the body off the pier and is accused of the murder. However he refuses to identify the woman who could prove his innocence.