THE ONION FIELD serves as both a true-life police thriller and a chilling indictment of the American judicial system. Two Los Angeles detectives in the 1960s stop a pair of shifty motorists. In a quick turn of events, one suspect pulls out a pistol, forces the cops to relinquish their guns, and drives them to an onion field. There, one detective is shot dead, while the other escapes. Although the suspects are soon caught, the road to justice proves bumpy, because each crook blames the other for the killing. Meanwhile, the detective who survived feels profound guilt and suffers a nervous breakdown. His condition threatens his ability to stay on the force and even propels him into making petty thefts -- not unlike those of the two men he first stopped.