The Cry Baby Killer (1958)

17-year-old Jimmy Wallace is brutally beaten by Manny Cole and two of his teen-age punk friends, Joey and Al, because Manny wants to move in on Jimmy's girl, Carole Fields. Later, Jimmy shows up at the hangout of the teenage crowd to take Carole away, and challenges Manny to a fight. Manny's two buddies move in with brass knuckles, and one of them pulls a pistol, which falls to the ground in the scuffle. Jimmy picks it up and shoots Manny and Al. A police officer orders Jimmy to surrender, but he panics, thinking he killed the pair, and dives into a small storeroom, and holds a man, woman and her baby as hostages...