Blake Stuerman, 30, has come forward about his “traumatizing” four years with Bryan Singer, the disgraced director of The Usual Suspects, Superman Returns, X-Men, and Bohemian Rhapsody. In a first-person account published in Variety, Stuerman details a sexual relationship that began in 2009—when he was 18 and Singer was 43—and ended with Singer firing Stuerman as his assistant in 2013.

Throughout the course of the relationship, Stuerman said he experienced “mental and emotional” abuse and was left traumatized after witnessing Singer allegedly assault someone in 2012. “I’ll fucking kill you if you leave me,” Singer allegedly told Stuerman at one point. Singer’s career has been stained by repeated allegations of sexual misconduct, including claims he raped a 17-year-old boy in 2003 and behaved inappropriately with minors on the set of Apt Pupil in 1998. He was also accused in a 2014 civil lawsuit that was later withdrawn of raping a minor.

Andrew Brettler, Singer’s lawyer, called Stuerman’s allegations “uncorroborated, inflammatory, and highly defamatory,” but did not deny that Stuerman had witnessed Singer assault someone or that the relationship began when Stuerman was just 18.