A narrator introduces himself as Harry Lockhart (Robert Downey, Jr.), a petty thief from NYC. He is self-aware and talks to the audience at various times through the movie. Running from the police after a botched robbery, he runs into a movie audition to escape and impresses the producers. He is brought to Hollywood and meets "Gay" Perry van Shrike (Val Kilmer), a flashy homosexual private eye who has to train him for his role as a detective in a movie. Lockhart and Perry get involved in a genuine intricate murder case with many leads. At a cocktail party Lockhart meets Harlan Dexter (Corbin Bernsen), once a B-movie actor and now a very rich enterpreneur whose daughter has only recently returned from a long sojourn to Paris. Harry also meets his high school sweetheart, aspiring actress Harmony Faith Lane (Michelle Monaghan), a girl who never cared much for him, but now she's seeing him with new eyes. The two leave for Harry's apartment, but budding romance is squelched when Harry proceeds to have sex with Harmony's friend. Harmony, Harry, and Gay team up to solve the mystery and encounter a series of seemingly nonsensical problems. They stake out a house to take photographs for a client, but they find a corpse. From there, twists and connections abound and bodies pile up. Then they uncover the sordid truth of the case.
Many critics admire this film for its clever comedy and Downey's and Kilmer's screen chemistry and performances. Mike Russell of the Portland Oregonian wrote: "This is one of Downey's most enjoyable performances, and one of Kilmer's funniest. It's a relationship comedy wrapped in sharp talk and gunplay, a triumphant comeback for Black, and one of the year's best movies." Jeff Otto, an IGN critic, wrote that, "It takes a bunch of genres and twists them into a blender, a pop relic that still feels current...one of the best times I've had at the movies this year." The title is a reference to Pauline Kael's 1968 book, which in turn was named after a translation of an Italian poster of a James Bond movie. The screenplay was written by Shane Black who also directed.
