Twenty-eight years after he was discharged from the army, Trapper John McIntyre, who was very much against authority, now finds himself the very thing he was against during the war as he is now chief of surgery at San Francisco Memorial Hospital. One day a young surgeon named G. Alonzo Gates (Gonzo for short), a former MASH surgeon and Vietman vet, walks into surgery and assists Trapper. Trapper then finds out that Gates is not a member of the staff. However, he is impressed with with the brash young doctor who reminds Trapper of himself when he was younger and hires him on the spot. Other members on the staff are Dr. Stanley Riverside (who's father was on the board of directors), intern Justin "Jackpot" Jackson, nurses Clara "Starch" Willoughby, Gloria "Ripples" Brancusi and Ernestine Shoop and, much later, Trapper's son J.T., who is working as an intern at the hospital.

A court ruled that the series was not a spin-off from the television show "M*A*S*H" (1972); rather, that it was a spin-off from the film MASH (1970).

Doctor "Trapper John" McIntyre:
Well, it's the money that counts, not the thought.