Suspicious Minds (1997)

Jack Ramsey (Patrick Bergin) is a private detective in the vein of Philip Marlowe who finds himself romantically involved with the woman he's supposed to spy on, and she's no good! Multiple murders take place and Ramsey makes it his goal to solve the complicated case while still retaining his own sanity, which is hard to do. Meanwhile the mysterious Vic Mulvey (Gary Busey) hides out in the woods touting an assault rifle, might he somehow be involved? You better make yourselves ready for one hell of a neo-noir-istic thrill ride, because this is it!