Nick Chinlund (Jeff Briggs / Jim Briggs), Dick Van Dyke (Dr. Mark Sloan), Barry Van Dyke (Detective Steve Sloan), Victoria Rowell (Amanda Bentley-Livingston), Annie Fitzgerald (Dina Briggs), Charmin Lee (Cheryl Banks), Phina Oruche (Asia), Deirdre Quinn (Teri Deegan)

Diagnosis Murder follows Dr. Mark Sloan, the chief of internal medicine, at LA's Community General Hospital. Dr. Sloan, much like Jessica Fletcher of Murder, She Wrote, has a magnetic quality that apparently draws murders to him. Every week, Dr. Sloan stumbles across murders, either acting in his role at the hospital, aiding the police as a medical consultant, or just plain dumb luck.

Episode 8.3
Mark is having a hard time preparing for a magic show for the child patients- first he misplaces the key of the chest he locked Steve in, then he learns janitor Jim Briggs, the magic talent, was killed surfing; his estranged, wealthy, married twin brother Jeff turns up just then. Mark soon suspects from various details it might just be Jim killed his brother to take his place, which sister-in-law Dina laughs away and suggests to Steve to take fingerprints, and then tells Jim she knew since the first day and was glad to be rid of Jeff; according to Jeffs will it also spares her losing two thirds of the estate to his sons from his first marriage. The Sloanes push on, helped by Jeffs secretary and mistress Teri Deegan.

Ник Чинланд (Джефф Бриггс / Джим Бриггс), Дик Ван Дайк (Доктор Марк Слоан), Барри Ван Дайк (Детектив Стив Слоан), Виктория Роуэлл (Аманда Бентли-Ливингстон), Энни Фитцджеральд (Дина Бриггс), Чармин Ли (Черил Бэнкс), Фина Оруч (Эйша), Дейрдре Куинн (Тери Диган)