Netflix is set to stream Should I Marry a Murderer? on April 29, a three-part documentary about Caroline Muirhead, a Glasgow-based forensic pathologist who discovered that the man she planned to marry had taken another man's life only a few years before they met.
The film, directed by Josh Allott, centers on the wrenching decision Muirhead faced in late November 2020 after her fiancé, Alexander “Sandy” McKellar, told her he had been involved in a homicide three years earlier and was on the run from it. McKellar then led her to the place where he had buried the body.
That disclosure landed in the middle of a life that was already under strain. Muirhead was 32 at the start of the pandemic in 2020, performing autopsies by day while still reeling from an abusive relationship at night. She had met McKellar on Tinder and described him as a seemingly eligible 31-year-old bachelor. Within five weeks, the pair were in a whirlwind romance and talking about marriage after just over a month together.
Allott said he first heard Muirhead’s story and thought it sounded like a drama rather than the real experience of a living person. The documentary frames that shock around a simple but devastating question: whether to protect a partner or report him to authorities.
Muirhead’s own words capture the pull of the relationship and the terror that followed. “Imagine you fall in love with someone who made you feel accepted, wanted, seen, who made you feel whole and loved and special, and you are just so happy,” she said. After she pressed McKellar outside as a police car passed by, she asked him, “What is it? What is going on? What is it you’re not telling me?”
The story matters now because the documentary turns a true-crime case in Scotland into a present-tense moral test rather than a simple account of past violence. By putting Muirhead at the center, Should I Marry a Murderer? asks what happens when love collides with the worst possible secret, and it answers the headline plainly: no, she should not marry a murderer.
