In 1990, the beheaded body of a young woman was found in a Rotterdam canal. The body remained unidentified until 2008, when new DNA techniques revealed that the victim was the American model Melissa Halstead. A joint investigation by the Rotterdam cold case unit and their colleagues in the United Kingdom led to John Sweeney. Sweeney is known to have a tumultuous relationship with Halstead – as evidenced by the many lurid drawings he made during their time together in Amsterdam.

• Documentary