The Sadist (1963)

Three teachers are on their way to a Dodgers game in Los Angeles but are forced to pull off to a gas station on the side of the road after their car gives them trouble. When they don't find the owner of the gas station, the three are startled by seeing a young man Charlie, holding a gun along with his girlfriend Judy. The couple have spent the past several days evading arrest and leaving a trail of corpses behind them. The couple terrorizes the teachers in broad daylight without any mercy.