The Long Goodbye (1973) on Netflix

Philip Marlowe is a chain smoking Los Angeles private investigator, quick with a one liner, and fiercely loyal to his friends. It is that loyalty which makes Philip grant the request of his long time friend Terry Lennox when Terry shows up on his doorstep late one evening: immediately drive him to the US-Mexico border into Tijuana. The next morning, Philip learns from LAPD that Terry's wife, Sylvia, has been murdered, Terry the primary suspect. Held in jail as an accessory to murder as he does not tell the police anything about his and Terry's latest encounter, Philip is released three days later as the police further tell him that Terry is dead by an apparent suicide in Mexico. Philip neither believes Terry murdered Sylvia or committed suicide. Not fully by his own choice, Philip gets further embroiled in Terry's story. Philip is visited by gangster Marty Augustine and his associates, who believe Philip has or knows where "his" money is that Terry had. Before that visit, Philip is hired by Eileen Wade to locate her husband, author Roger Wade, who has been missing for a week, who has a penchant for over-imbibing, and who has a violent streak when he's drunk as witnessed by the bruise on Mrs. Wade's face. As she believed, Philip is able to locate him in one of the region's many high end private detox clinics, those where he often frequents after especially destructive drunken sprees. It's the casual acquaintanceship the Wades had with the Lennoxes about which Eileen admits to Philip that Philip later learns is much more that makes Philip believe the Wades are also tied into the death of the Lennoxes in some manner, either directly or indirectly. Philip has to tie the pieces together, including discovering what happened to Augustine's money, before Augustine makes good on his threat against him.