Born in a southern suburb of London shortly after the end of World War II, Simon Anthony Lee Brett is the son of John Brett, a surveyor, and Margaret Lee, a schoolteacher. His secondary education was at Dulwich College, where he won a scholarship to Wadham College, Oxford, to study history. He graduated with first class honors, but only after serving as president of the University Dramatic Society and as director of the Oxford Late-Night Revue on the Fringe at the Edinburgh Festival. He married Lucy Victoria McLaren in 1971, and they subsequently raised two sons and a daughter.
In 1968, Brett became a radio producer for the British Broadcasting Corporation (BBC). He also began writing plays. His first production, Mrs. Gladys Moxon, debuted in London in 1970. His next play, Did You Sleep Well? was staged the following year and another, Third Person, in 1972. His interest in plays gave way to radio and television scripts, earning him the 1973 Writers Guild of Great Britain Award for the best radio feature script, and then he decided to branch out into novels. While with the BBC, he produced the first episode of The Hitchhiker’s Guide to the Galaxy (1978), a radio series.
The BBC assigned Brett to produce a series of adaptations of Dorothy L. Sayers’s Lord Peter Wimsey mysteries. Brett says he worked closely with the writer who was adapting the books into scripts and his experience “sort of demystified the genre.” This association with the Wimsey project showed him that a good mystery is series of dialogues, with the sleuth interviewing various characters: “If you can actually make the dialogue interesting, there is usually one fact that has to emerge from these encounters; . . . the top wasn’t on the bottle of whiskey . . . and you can make an interesting scene around that.” Although he was not sure of his ability to create the puzzle plots typical of mysteries, he knew that he could write dialogue and decided to write a mystery.
Brett published his first mystery, Cast, in Order of Disappearance, the start of the Charles Paris series, in 1975. In 1986, after eleven years of producing a Charles Paris novel annually, Brett created a new series featuring Mrs. Pargeter. In 2000, he started a third, featuring two women in the coastal town of Fethering.