Dormer co-wrote the film "In Darkness", released in July 2018, with her ex-fiancé Anthony Byrne. Each describe writing together as "challenging". The film was criticised for scenes of "gratuitous nudity". During an interview with "The Guardian", she says "There has to be sex in the power play of a thriller. We all got bodies, after all. In this film, the love-making scene is a metaphor for the way my character connects with the part played by Ed Skrein. Nakedness is a good equaliser, and the shower scene also shows the tattoos on my character’s body and makes it clear she is not quite who you think."