Michael Gothard was born in London in 1939. As a child, he lived in both Wales and London. After leaving Haverstock School, he travelled in France for several months before returning home. He went through various jobs, including being a building labourer and a trainee reporter. He even had a brief spell as a clothes model, but he never felt comfortable doing that job. He said: "I was as stiff as a board and I couldn’t overcome my sense of the ridiculous. I was a clothes hanger, an object, not a person."

He joined the New Arts Theatre as a scenery mover, and became part of an amateur film a friend was making. After landing the lead role, he was encouraged to take up the profession. He attended evening classes at an actors' workshop whilst holding down a day job. He was involved working in some of the first "Lunchtime theatre" productions in the 1960s, from pub cellars to top floor spaces off St. Martin's Lane. His first television role was in an episode of Out of the Unknown in 1966 called "The Machine Stops". He was then cast in Don Levy's film Herostratus in 1967 and Up the Junction in 1968. He then acquired a female following after taking a role as the villainous Mordaunt in the BBC's adaptation of Twenty Years After (Further Adventures of the Musketeers).

He had a regular role as Kai opposite Oliver Tobias's King Arthur on the aforementioned Arthur of the Britons during the early 1970s. He became known to a wider cinema audience for his menacing turn as the villainous (and non-speaking) Belgian henchman, Emile Leopold Locque, in the 1981 James Bond film, For Your Eyes Only. Gothard was actually the one who suggested Locque's signature octagonal glasses in an effort to make the character more menacing. His later appearances included supporting roles in Tobe Hooper's 1985 science-fiction horror extravaganza, Lifeforce, and as George Lusk in the 1988 TV movie, Jack the Ripper, with Michael Caine. He appeared with Dean Stockwell and Shirley Knight in a Hammer House of Mystery and Suspense (a.k.a. Fox Mystery Theatre) episode, The Sweet Scent of Death. His last few roles were in Christopher Columbus: The Discovery in 1992, where he briefly acted opposite Marlon Brando. It was directed by his For Your Eyes Only Director John Glen, but was a box office failure.

He appeared in Ken Russell's 1971 horror film, The Devils, in which Gothard had a stand-out role as a fanatic witch-hunter and exorcist who defiles Vanessa Redgrave and tortures Oliver Reed. His performance as a young disillusioned hippie in Barbet Schroeder's La Vallée (1972) contrasted with the rest of his career. He also played a fictionalised version of the 17th century Assassin John Felton in Richard Lester's 1973 film of The Three Musketeers and its 1974 sequel, The Four Musketeers.

Gothard, who struggled with depression for much of his life, committed suicide by hanging on 2 December 1992. He was fifty-three years old.

His performance as the nightclubbing killer Keith in Scream and Scream Again, directed by Gordon Hessler, was a break-out role for him, giving him exposure and leading to other, more prominent parts. In the film, Keith makes one of the most memorable escapes from the police ever seen. The film also starred Vincent Price, Peter Cushing and Christopher Lee. Executive Producer Louis M. Heyward said of Gothard's performance: "I felt that Michael Gothard was going to be the biggest thing that ever happened. He had that insane look and that drive, and he was wonderful. Here is a kid who really threw himself into the picture wholeheartedly. Do you remember the scene where he appears to be walking up the cliff? That's a stunt that, as an actor, I would not have agreed to; I’d say, 'Hey, get a double or get a dummy. I ain't either one.' But the kid agreed to do it, without a double—he was that driven. He had a lot of class and a lot of style. Gordon (Hessler) came up with the idea of using an overhead cable to give that illusion of his walking up the cliff."