It’s well-proven that Emmy winner Jodie Comer excels at accent work.

The actor’s Russian accent as psychopathic assassin Villanelle in “Killing Eve” was so good that playwright Suzie Miller nearly passed on her to star in “Prima Facie” because the play was written for someone from Liverpool.. Now, in Jeff Nichols’ latest film, “The Bikeriders,” about the rise and fall of a Midwestern motorcycle club in the 1960s, she puts on a working-class Chicago accent to play Kathy, a strong-willed woman who falls for a free-spirited biker named Benny (Austin Butler) and finds herself competing with Johnny (Tom Hardy), the club’s leader, for his attention and devotion.

The Searchlight movie is inspired by the 1967 photography book “The Bikeriders” by Danny Lyon, who captured the story of the Vandals motorcycle club. He’d recorded interviews with members of the club too, so Comer had about 30 minutes of the...