Handlung

In 1947, a smart-mouthed Brit working in L.A. as a private eye (or peeper) is on a case to find the long lost daughter of a shady client pursued by two dangerous goons. The case leads him to a rich oddball Beverly Hills family.

The film is set in Los Angeles in 1947. A criminal (Michael Constantine) on the run from hired killers comes to the office of a private detective named Tucker (Michael Caine) and asks Tucker to find a daughter he left at an orphanage in 1918. The man has a substantial amount of money that he wants to give the girl. Tucker's search leads him to two sisters (Natalie Wood, Kitty Winn), daughters of a rich Beverly Hills widow (Dorothy Adams). Tucker is sure one of the sisters is the man's daughter, but he's not sure which is the right one. Meanwhile, the killers chasing Tucker's client are now chasing the detective, and Tucker also discovers that the widow's brother-in-law (Thayer David) may be blackmailing the two girls and/or embezzling from the widow. Tucker also keeps encountering a mysterious stranger who seems to know more than he admits, and may or may not be working with the brother-in-law. Ultimately everyone ends up on a cruise ship headed to South America and the various mysteries are resolved.

In 1947, Hollywood, California, Lou Anglich (Michael Constantine) climbs a spiral staircase and realizes he is being followed. Swinging around, he smashes his briefcase over the other man's head, before throwing him over the railing. The man falls, but grabs a banister, pulls himself up and runs down a hall. Leslie C. Tucker (Michael Caine), an English private detective, or "peeper," hears the commotion and goes into the hallway to have a look. Upon returning to his office, he finds Anglich, who says he put his daughter, Anna, in an orphanage 29 years ago and wants Tucker to find her. Their conversation is interrupted by the sound of men prowling the halls. Anglich kills the lights, locks the door and tells Tucker to be quiet. Once the men move on, Anglich tells Tucker that he made a lot of money in Florida and wants to give it to his daughter before his "business associates" find and kill him. After Tucker takes the case, Anglich shows him a photograph of a young Anna and Fred Conroy, the man who supposedly adopted her, standing by a stone gate displaying a street number. Anglich explains that he recently located Jasper, the former head of the orphanage, but when he went to Jasper's office, three men attacked him. The next day, Tucker finds a house in Beverly Hills that matches Anglich's photograph. Tucker enters the house through an open door and finds Franklin "Frank" W. Prendergast (Thayer David) in the atrium surrounded by birds. Frank's sister-in-law, and owner of the home is bedridden and does not receive guests. Posing as a reporter, Tucker shows Frank the photographs and learns the man in the photo is Frank's dead brother, Harry. As they talk, Tucker sees Ellen Prendergast (Natalie Wood), who adjusts her silk robe, giving him an ample view of her body. She gives him a smile, then disappears. Frank orders Tucker to leave when he refuses to explain how he came by a photograph of Harry. As he crosses the courtyard, a snarling Doberman pinscher leaps at Tucker, but is restrained by Ellen's sister, Mianne Prendergast (Kitty Winn). As Mianne and Tucker talk, Ellen appears on the balcony and beckons him inside. However, when Tucker finds Ellen, but she claims ignorance of any Fred Conroy and takes him to meet her mother, Margaret Prendergast (Dorothy Adams), who is having breakfast in bed. When Tucker shows Margaret the photographs, she rubs jam on them and spits at Tucker, screaming for him to leave. Before Tucker goes, Ellen makes a date to meet with him the next day. Unaware he is being followed, Tucker returns to his office and receives a telephone call from Anglich claiming to be in trouble. Tucker drives to a pool hall, where a battered Anglich explains that three assailants attacked him at a bar. He killed one and left the other two unconscious. Thinking he may not have long to live, Anglich mailed a package to Tucker which he is to give to Anna. If Tucker is unable to find the girl before Anglich is killed, he can keep it. Tucker decides to talk to Jasper, the orphanage head, but when he gets to the office building he discovers Ellen in the lobby and Jasper's dead body in the office. As Ellen explains that she received a telephone call asking her to meet Jasper, Rosie (Don Calfa) and Sid (Timothy Carey), two of the men who earlier attacked Anglich, appear and beat Tucker. Ellen hits Sid with a milk bottle, allowing Tucker to pull his gun. The two thugs take Ellen hostage, but Tucker gives chase, ending in a burlesque house, where Sid and Rosie abandon Ellen and escape. Before she leaves, Tucker reminds Ellen of their date. Tucker returns to his office and finds Billy Pate (Liam Dunn), a skinny old man, rummaging through his papers. Pate is Jasper's lawyer and, if Tucker will give him "the memo," Pate will help him parlay it into millions of dollars. Tucker throws Pate out after Anglich telephones to say he has found Anna. The next day, Tucker keeps his date, but instead of Ellen, Mianne appears and claims Frank is blackmailing her with information that she is not Margaret's daughter. According to Frank, Margaret Prendergast had twin girls out of wedlock and placed them in an orphanage. When she later married, Frank Prendergast went to retrieve the twins, but discovered one had already been adopted by a family named Conroy. Frank took Mianne, claiming she was the other lost daughter. Mianne hires Tucker to stop Frank from blackmailing her. Back at the office, Tucker finds Anglich dead. Hearing a noise, he goes to his waiting room to find a mailman delivering Anglich's package. As Tucker signs for the package, Ellen arrives to explain that Frank is also pressuring her to get her mother to give Frank power of attorney, so he can rob her. The telephone rings, but no one is on the line, prompting Tucker to grab both the package and Ellen, before running run out of the office. Taking the stairs to the basement, they become separated. Rosie, the thug, gets the drop on Ellen, until Tucker arrives and they exchange gunfire. Tucker grabs Ellen and hides in a closet. While Rosie and Sid search for them, Tucker and Ellen embrace. Once they know the coast is clear, Ellen hits Tucker with his own pistol, but cannot wrestle the package from him. Hearing a noise, Ellen runs away, leaving Tucker to open the package and discover a suitcase full of money. That night, Tucker returns to the Prendergast home and catches Billy Pate searching Frank's room. Although Billy refuses to say why he is there, he discloses that Frank is taking the girls and Margaret out of the country on a cruise ship that leaves in an hour. Tucker drags Pate to his car and notices Sid and Rosie's automobile blocking the gate. Tucker smashes the other car out of his way and races off with Sid and Rosie in pursuit. A high-speed chase turns into a crawl as both cars get caught in traffic. Pate takes the opportunity to leap out just as Sid leaps in brandishing a gun. Tucker punches Sid unconscious, only to have Rosie pull up beside him and open fire as the two cars weave slowly in and out of traffic. Rosie hits a truck carrying cars. One of the automobiles breaks free and lands on his hood. Rosie climbs out of the wreckage and steals a car. When he gets to the dock, Rosie locates Tucker's car with Sid stuffed in the trunk. Meanwhile, carrying the suitcase full of money, Tucker boards the ship and spots Pate in a telephone booth. After threatening to strangle Pate, Tucker learns that Frank and Ellen are stealing from Mrs. Prendergast. Pate escapes and as the ship leaves port, Tucker goes to the Prendergast's state room and finds Frank, Ellen and Mianne, who is dressed in a grey wig and drugged unconscious on the bed. When Tucker announces he has solved the mystery, Pate enters, then runs away. Tucker, Frank and Ellen chase Pate through the ship and into the dining room, and are shocked to find Margaret Prendergast eating dinner. Margaret asks them all to be seated and explains that when Billy Pate learned that Frank was blackmailing her biological daughter, Ellen, into extorting money from her, he offered to work as her double agent. Ellen grabs the suitcase full of money and runs out onto the ship's deck where she is grabbed by Sid and Rosie. As she struggles, she throws the suitcase into a lifeboat. Tucker appears and all three men leap into the lifeboat, knocking the suitcase back onto the deck. Ellen pulls a lever, sending the boat into the sea. However, Tucker grabs a rope and climbs back aboard. He finds Ellen on the poop deck and takes back the suitcase. He tells her he is giving the money to Mianne after he has a drink. Ellen joins him at the bar as Sid and Rosie row by in the lifeboat.