Philip Marlowe (James Garner) is engaged by the exotically named Orfamay Quest (Sharon Farrell) to find her brother, Orrin, who has been missing for some time and whom she believes to be in trouble. Marlowe soon finds a hoodlum associate of Orrin's, Grant Hicks (Jackie Coogan). Hicks is then murdered, and Marlowe, who finds him dead in a flophouse hotel, discovers photos of one Mavis Wald (Gayle Hunnicutt)—a well-known television actress—in compromising positions with mob boss Sonny Steelgrave (H.M. Wynant). With occasional assistance from Mavis's friend Dolores (Rita Moreno), a stripper, Marlowe sets out to find Orrin's whereabouts and solve the murders.
Bruce Lee, in the first film of his too-short movie career, has two scenes as Winslow Wong, a badass martial artist (of course) sent by Steelgrave to intimidate Marlowe. William Daniels appears as Mavis's agent.
- Almost Dead Guy: Marlowe hears a gunshot in Lagardie's office, goes to investigate, and finds Orrin. Orrin has been shot, and he has just enough life left to stick his icepick in Marlowe's back before he falls over dead.
- Artistic License Gun Safety: Marlowe, at the scene of a murder, checks that a gun has been fired by putting the muzzle under his nose and smelling it. Yes, his finger isn't on the trigger, but he certainly should know better.
- Attentive Shade Lowering: Marlowe drops his shades below his eyes in dry disbelief upon stepping out of his car and seeing the Infinite Pad.
- Badass in a Nice Suit: The title character aside, there is Winslow Wong. When Marlowe refuses his Bribe, Winslow tears apart his office with his bare hands.
- Blackmail: Orrin took the pictures of Mavis and Steelgrave in order to blackmail his own sister.
- Deadly Dodging: Winslow Wong is defeated when he attempts a flying kick on Phillip Marlowe while they are a balcony. Marlowe dodges, causing Wong to fly over the edge to his death.
- Deadpan Snarker: Marlowe as always, like when he's mocking Wong's fastidious use of "whom."Marlowe: I like a man who uses good grammar. You impress me, Mr. Wong. Whom sent you?
- Destroy the Evidence: Marlowe does this twice. First, he tears up the blackmail photos of Mavis and Steelgrave, then burns them and the negatives in his office wastebasket. Then, later, he wipes Mavis' fingerprints off the gun, phone and bar glasses at Steelgrave's home, after Steelgrave's murder.
- Disney Villain Death: Winslow Wong has Marlowe cornered on the edge of a balcony high up on a skyscraper, but after Marlowe dodges Wong's flying kick, Wong goes plunging to his death.
- Driving a Desk: When Marlowe is riding to and from the airport in Mr. Crowell's limo, and when he and Delores are riding to Steelgrave's house.
- Frame-Up: Turns out that Dolores shot Steelgrave with Mavis's guns and then lured Mavis to the scene in order to implicate her as the murderer.
- Impairment Shot: The screen goes all distorted after Marlowe is drugged by Dr. Lagardie.
- I Shall Taunt You: Marlowe goads Winslow Wong into attempting his fatal flying kick by insulting him over and over, ending with calling him gay.
- Knight in Sour Armor: Marlowe as in the books. Despite his general world-weariness and sarcasm, he's honorable, like when he rejects Orfamay's offer of sex for payment or when he rejects the bribe money that Wong delivers from Steelgrave.
- Laser-Guided Karma: Dolores kills Steelgrave for leaving her and hooking up with Mavis. Then Dr. Lagardie kills Dolores for leaving him and hooking up with Steelgrave.
- Love Makes You Evil:
- It turns out that Dolores killed Steelgrave out of jealousy. Steelgrave, her former lover, dumped her for Mavis. Her jealousy of Mavis for hitting it big as an actress when Dolores is stuck as a stripper is another motivator.
- Then Dr. Lagardie, Dolores's husband, kills her out of jealousy.
- My God, What Have I Done?: Late in the film, Lt. French has had enough of Marlowe's snarkiness and interference in a police investigation. He throws a punch at Marlowe, but hits his partner Sgt. Beifus by mistake. French is shaken and immediately apologizes for hitting him. Beifus replies, "Nobody hit me, Christy. Nobody I can remember."
- Screw the Money, I Have Rules!: Steelgrave has Winslow Wong offer Marlowe $500 (which was a lot of money in the 1960s) to stop his investigation. He refuses and tells Wong to take the money back.
- Setting Update: Moves the story from the novel's 1949 to 1969, turning Mavis from a movie actress to a TV actress. Absolutely reeks of The '60s, with hippies and people saying "You dig?" and the like.
- Sex for Services: Orfamay, who comes across as an innocent Kansas girl, makes a surprising offer of sex to Marlowe when she can't come up with more than $50 to pay him. Later it turns out she's not nearly as innocent as she pretends.
- Shout-Out: Grand Hotel is playing at the television studio when Marlowe goes to meet Mavis's agent.
- Slipping a Mickey: Dr. Lagardie gives Marlowe a cigarette that is laced with something, knocking Marlowe out.
- Split-Screen Phone Call: A comic relief scene has Marlowe calling a pawnbroker on one phone when his girlfriend Julie calls him on another phone; the screen is split three ways as Marlowe tries to carry on two conversations at once.
- Threat Backfire: Late in the movie, an angry Lt. French threatens to take away Marlowe's P.I. license. Marlowe is unfazed, as he knows French doesn't have the authority to do it, which makes French even angrier.