© Rex Features / Steve Pohlner/Newspix
The rapper/actor joins Woody Harrelson and Ben Foster in the film directed by Oren Moverman.
Rampart is based on a real-life scandal involving Los Angeles police officers in the 1990s.
Cube will play a homicide detective sent to investigate a corrupt cop (Harrelson).
The movie is scripted by Street Kings screenwriter James Ellroy.
