Gilbert was a lawyer in London for many years and at one point had Raymond Chandler as his client. He had a very long and very productive writing career, beginning with his first novel, Close Quarters, in 1946 and continuing through 1999 with Over and Out. He wrote almost every sort of mystery and thriller, perhaps spreading himself too thin over too many fields to achieve the reputation that many critics felt he deserved. He wrote police procedurals, spy novels and short stories, courtroom dramas, classical mysteries, adventure thrillers, crime novels, and almost every possible combination of these, all with the same competence and dry, detached wit.

Perhaps among his very best books are two collections of short stories about two gentlemanly but exceedingly hard-boiled fictional British counterspies, Mr. Calder and Mr. Behrens, "middle-aged cut-throats" as one of their adversaries bitterly refers to them. One of his earliest novels, Smallbone Deceased, is also highly regarded by many.

Michael Gilbert was educated at Blundell's School and the University of London, where he read Law. After a spell teaching at a prep school, he joined the Honourable Artillery Company when war broke out, serving in North Africa and Italy. In 1943 he was captured and imprisoned in northern Italy, escaping after the Italian surrender.

He is the father of the writer and broadcaster Harriett Gilbert and the Independent journalist Gerard Gilbert.

Mystery novels

• Close Quarters (1947)
• They Never Looked Inside (1947) [U.S. He Didn't Mind Danger (1948)]
• The Doors Open (1949)
• Smallbone Deceased (1950)
• Death Has Deep Roots (1951)
• Death in Captivity (1952) [U.S. The Danger Within]
• Fear to Tread (1953)
• Sky High (1955) [U.S. The Country-House Burglar]
• Be Shot for Sixpence (1956)
• Blood and Judgment (1959)
• After the Fine Weather (1963)
• The Crack in the Teacup (1966)
• The Dust and the Heat (1967) [U.S. Overdrive (1968)]
• The Etruscan Net (1969) [U.S. The Family Tomb (1969)]
• The Body of a Girl (1972)
• The Ninety-second Tiger (1973)
• Flash Point (1974)
• The Night of the Twelfth (1976)
• The Empty House (1978)
• Death of a Favourite Girl (1980) [U.S. The Killing of Katie Steelstock]
• The Final Throw (1982) [U.S. End-Game]
• The Black Seraphim (1983)
• The Long Journey Home (1985)
• Trouble (1987)
• Paint, Gold and Blood (1989)
• The Queen Against Karl Mullen (1991)
• Roller-Coaster (1993)
• Ring of Terror (1995)
• Into Battle (1997)
• Over and Out (1998)

Collections of short stories

• Game Without Rules (1968)
• Stay of Execution (1971)
• Amateur in Violence (1973)
• Petrella at Q (1977)
• Mr. Calder and Mr. Behrens (1982)
• Young Petrella (1988)
• Anything for a Quiet Life (1990)
• The Man Who Hated Banks (1997)
• The Mathematics of Murder (2000)
• The Curious Conspiracy (2002)
• Even Murderers Take Holidays and other mysteries (2007)
• A Pity about the Girl and other stories (2008)

Details of other short stories can be found in B. A. Pike, The Short Stories of Michael Gilbert. An annotated checklist, 1948-1997 (CADS: South Benfleet, Essex, 1998).