The chalk-and-cheese detective duo are called to a private clinic where a wealthy patient has been killed. However, their investigation is made all the more difficult by the complex relationships…

Jack and the team uncover a nest of vipers when a zoo owner is killed with a tranquiliser dart and everyone has an alibi.

Lucille must win the trust of a mother who is terrified of giving birth. Nurse Crane and Dr Turner are anxious to find a possible smallpox sufferer.

Barbara gets involved with a recently widowed pregnant woman, and Sister Monica Joan has her cataract surgery.

Dr Turner gets involved with a troubled young man, and Lucille makes new friends. Meanwhile, Barbara lies ill in hospital.