Black and White (1999)

Chris O'Brien, devote Catholic and rookie cop with LAPD, is assigned to partner with the hard-edged, street-smart Nora Hugosian. A serial killer is loose, and all the victims are low-life guys whom Nora has dealt with. So, when the tire tracks of a police car are found at a murder scene, she's the prime suspect of internal affairs investigator Simon Hertzel. Chris and Nora start an affair, but meanwhile he has suspicions about her. Should he start his own investigation, which would be an act of betrayal, or trust her, as his partner and his lover? When a witness i.d.'s Nora's former partner, Michael Clemence, as the killer, Nora gives Mike an alibi, and things get complicated.