"Beware of the Dwarf", whispers the hitchhiker- turned-date, to the beautiful librarian, Gloria Mundy (Goldie Hawn), as he dies in her lap, bleeding amidst the popcorn, midway through a screening of "This Gun Is Mine," at the Nu-Art Theater. Suddenly, Goldie finds herself in a crazy world of "wild chases, bizarre attempts on her life", and scary, "deadly encounters with an assortment of weird underworld characters," all because she followed the advice of her girlfriend, who, at a prenuptial party, told her to come out of her divorce shell-shocked state, and once again take some chances with dating men again.
Her adventures began after picking up a handsome hitchhiker with car trouble, who is an undercover cop, on her way back to San Francisco, where she works and lives. She doesn't notice that a black sedan is following her. Before dropping him off in the city, Scotty gives her his cigarette pack, because he is trying to quit. Inside the pack is a roll of exposed film hidden inside, that Gloria doesn't know about or notice. The film is the gathered evidence against the bad guys who are about to attempt an assassination of the Pope. Scotty and Gloria decide to go to see a movie together, where she would give him back the cigarettes.
When Scotty fails to meet her, she goes inside the theater. He finds her in the theater, sits down next to her, tries to warn her about an upcoming murder, and warn her about the bad guy who shot him. She thinks he is talking about the film, but when he dies in her lap, she screeches and goes to find the theater manager. When he stops the film and turns on the lights, Scotty's body is no where to be found.
She finds herself that same night being chased by an albino thug, but she escapes into a bar where she asks Stanley Tibbits (Dudly Moore) to take her to his place. Humor reigns at Tibbits apartment. For now she was safe.
However, during closing time at the library the next day, Gloria is attacked by the albino man, Whitey Jackson (William Frankfather) who tries to knock her out with Chloroform. She manages to escape. She goes home to be surprised by a scary man, Scarface (Don Calfa) in her bathroom, asking her for the pack of cigarettes. While he tries to strangle her, she fights back and sticks him with her knitting needles, wounding him. As she is calling the police, her attacker approaches her with a firepower, but he is stabbed by a flying knife thrown at him through the window by, you guessed it, Whitey Jackson. Gloria Faints.
When she awakes, she finds Tony Carlson (Chevy Chase), a handsome, San Francisco police detective sitting beside her. This same Tony had already met Gloria at the above-mentioned prenuptial party, and had struck out socially with Gloria Mundy (Goldie Hawn). Now, Tony and his partner, Fergie (Brian Dennehy) find themselves unexpectedly becoming personally and professionally involved with all the "odd things" happening to Gloria, as the plot thickens, though at first no one believes her story, not even Gloria's apartment manager and good friend, Mr. Hennessey (Burgess Meredith). Everything was cleaned up, and again there was no dead body.