Following the success of his first three films, Dario Argento curated and produced a series of four medium-length films, each approximately an hour long, for RAI. In addition to presenting each episode, the director himself directed one of them, The Streetcar, also taking over from Roberto Pariante as director of Eyewitness. The other two films were directed by Luigi Cozzi, a collaborator of Argento's, and Mario Foglietti.
Luca and Stefania and their newborn baby move to a house on the Lazio coast, unaware that their neighbor has just killed his wife.
A young police commissioner investigates the murder of a young woman, which occurred the previous night in a tram car. To solve the case, the commissioner is willing to do anything, even risk his girlfriend's life.