Jeffrey Wright and Mos Def sign on to star in the mystery film, Little Scarlet for HBO Films and Picturehouse.

The film is based on the 2004 novel from Walter Mosley about Rawlins, a janitor and unlicensed private eye, and Mouse, a killer who helps Rawlins crack cases; Variety says Little Scarlet is considered one of the strongest in the mystery series. The film takes place in L.A. right after the 1965 Watts riots. White cops, afraid to poke into the murder of a black woman when the suspect is a white man she sheltered, draft Rawlins to investigate.

The two roles were originated by Denzel Washington and Don Cheadle in Carl Franklin's 1995 film Devil in a Blue Dress. Mosley is writing the script; Wright and Def haven't decided who'll play which role. There's no production schedule set for Little Scarlet.