Sheila Garvie was born Sheila Watson and grew up in Scotland. She married Maxwell Robert Garvie in 1955. They lived at West Cairnbeg Farm in Kincardineshire. The couple had three children together. Initially, their life seemed normal, but it changed in the 1960s.

Max became interested in pornography and nudism. By 1964, he had helped establish a nudist club on their farm. Sheila expressed discomfort with Max’s sexual demands, saying they were “abnormal.” This caused tension between them. In 1967, Sheila met Brian Tevendale, a 22-year-old who began to help out on the farm during weekends. Tevendale introduced his sister, Trudy Birse, to the Garvies, and the four of them began to engage in sexual activities together.

The situation caused local gossip, especially since Trudy was married to a policeman. In March 1968, Sheila left with Tevendale for Bradford, but Max found her and convinced her to come back. Just a few months later, on May 15, 1968, Max was reported missing. His last known location was at a meeting for the Scottish Nationalist Party the night before.

Sheila later confided in her mother that she suspected Tevendale of being involved in Max's disappearance. At that point, the police were informed. They began searching and discovered Max's body shortly after. Sheila, Brian, and another friend were arrested and faced serious charges. Their trial became a significant event in Aberdeen, drawing much public attention due to the circumstances surrounding Max's death and Sheila and Brian's relationship.

On May 19, 1968, Maxwell Garvie was reported missing by his sister, Hilda Kerr. He was last seen on May 14 at a Scottish Nationalist Party meeting. His car was found parked at a flying club, but searches for him in the woods and wells revealed no trace.

Eventually, Sheila Garvie confessed to her mother that Maxwell was dead and suggested that Brian Tevendale was involved in his disappearance. Following this, Sheila's mother contacted the police. On August 16, 1968, police arrested Sheila Garvie, Brian Tevendale, and Alan Peters, a friend of Tevendale. The next day, Maxwell Garvie's body was discovered in an underground drain near Lauriston Castle. He had been bludgeoned and shot in the head.

During the trial in November 1968 at Aberdeen High Court, details emerged about relationships between Maxwell, Sheila, and Tevendale, which included affairs and sexual activity. Testimony revealed that after a night of drinking, Sheila had let Tevendale and Peters into the house, which led to the murdered man's death as he slept in bed.

The jury returned a not proven verdict for Alan Peters, while both Sheila Garvie and Brian Tevendale were found guilty of murder. They both received life sentences. In 1978, they were released from prison.

After their release, Brian Tevendale became the landlord of a pub in Perthshire and died in 2003. Sheila Garvie remarried twice and managed a bed-and-breakfast in Stonehaven, leading a much quieter life than she had before.