Angie Dickinson stars as Kate Miller, a housewife so unsatisfied sexually that she often finds herself having vivid and wild sexual fantasies, with violent overtones. She has been seeing a psychiatrist, Dr. Elliott (Michael Caine), about her marital problems, and even makes a pass at him, although nothing comes to pass. Unable to resist the temptation, Kate has an afternoon fling with a complete stranger, only to end up the victim of a brutal and senseless slaying at the hands of a mysterious figure with a straight-edge razor. Only one person witnessed the murder, a spunky prostitute named Liz (Nancy Allen), who describes the perpetrator as a blonde woman in sunglasses. Meanwhile, Dr. Elliott begins receiving phone calls from one of his patients, Bobbi, a pre-op transsexual with homicidal tendencies, and Dr. Elliott’s stolen razor.
The Brody family, not led by the widow Ellen Brody (Lorraine Gary), continues to experience shark attacks, starting with when Ellen’s younger son, Sean. While mourning the loss, Ellen visits her other son, Michael (Lance Guest), in the Bahamas, where she meets the rascally Hoagie Newcombe (Michael Caine). Meanwhile, the same shark that got her boy appears off the coast of the island, and Ellen has to take it down or never escape the shark’s wrath. Mario Van Peebles also appears in this Joseph Sargent film so bad that it killed off the Jaws franchise once and for all.