Frank Levin is a private investigator for defense attorneys in the state. Levin worked many cases for Michael Haller, including the Louis Roulet case. Levin was responsible for uncovering both evidence that would assist Louis Roulet in trial, but also uncovered evidence connecting Louis Roulet with the sexual victimization and murder of prostitute Martha Renteria. This evidence led to Levin's murder at the hands of Roulet's mother, Mary Alice Windsor.