James Mason & Dan Duryea in "One Way Street" (1950) -feat. William Conrad & Rock Hudson (uncredited)

Sirens shriek through the Los Angeles nightscape while, from the window of an apartment building, an elegant woman, Laura Thorsen (Märta Torén), smokes as she stand at an apartment window, watching them disappear. Dr. Frank Matson (James Mason) is on a house call to gangster John Wheeler (Dan Duryea), who has just masterminded a bank robbery.

Matson gives Wheeler some pills for his headache, calmly picks up the medical bag containing the proceeds of the robbery and tells Wheeler that the pills he swallowed contain poison. After promising to telephone him with the antidote, Matson and WHeeler's lover, Laura, drive away.

One of the gang, Arnie (Jack Elam), is hiding in the back seat of the car, and demands the money. While Laura drives, Matson wrestles with Arnie and kills him. He then reveals that the pills he gave to Wheeler were harmless. Laura crashes the car. The police arrive. Matson claims Arnie was a hitchhiker killed during the accident.

Later, Matson and Laura buy a used car and continue toward Mexico, and hire a plane, which breaks down near a small village. A priest, Father Moreno (Basil Ruysdael), offers them food and scares off bandit brothers, Francisco (Rodolfo Acosta) and Antonio (Margarito Luna) Morales.

Later, Capt. Rodriguez (George J. Lewis) arrives with his men. Moreno takes Laura and Matson to a village where the pilot can buy the parts to fix the plane, and asks Matson to help a small sick girl. Matson reluctantly agrees, sparking a fight with medicine woman Catalina (Emma Roldán), but the girl is already dead. Matson tells Laura he unsuccessfully tried to save the life of a woman he loved.The girl's brother, Santiago (Robert Espinoza), says the village horse is sick. Matson volunteers to help. The ailing horse recovers and when the plane arrives, Matson bows to the pressure of Laura and the village children and stays behind, not traveling on to Mexico.

Later, one of Wheeler's henchmen, Ollie (William Conrad), questions the pilot, who tells him that Laura and Matson went to Mexico City.

After several weeks, Rodriguez and Moreno arrive with supplies for the village hospital. The Morales brothers interrupt an operation. Santiago intervenes, one of the brothers shoots him, and is shot in turn by the soldiers. Matson decides to return the money, settle things with Wheeler, and promises to allow Moreno to conduct a private marriage ceremony when he returns.

Together Laura and Matson travel to California. Matson tells Laura how much he loves her and knowing her has made his life worthwhile. Matson learns that Ollie killed Wheeler, and now intends to kill Matson. Matson shoots Ollie, then returns to Laura, but is hit by a car and killed.

A 1950 American Black & White film-noir crime film (a/k/a "Death on a Side Street") directed by Hugo Fregonese, produced by Leonard Goldstein, written by Lawrence Kimble, cinematography by Maury Gertsman, starring James Mason, Märta Torén, Dan Duryea, Basil Ruysdael, William Conrad, Rodolfo Acosta, King Donovan, Robert Espinoza, Tito Renaldo, Margarito Luna, Emma Roldán, George J. Lewis, and Jack Elam. Screen debut appearance of James Best.

James Best was born Jewel Guy (1926 – 2015).

Rock Hudson (Roc Hudson) has a tiny early role as a truck driver (uncredited).

Rodolfo Acosta, Margarito Luna, and Emma Roldan were all Mexican actors.

Märta Torén (1925 – 1957) was a Swedish stage and film actress of the 1940s and 1950s. Torén's father was a Swedish military officer, and for three years, during World War II, he was a secretary in the Swedish war office. After studying at the Stockholm Royal Dramatic Theatre's Royal Dramatic Training Academy, Torén began her career on the stage and from 1947 she appeared in films. She appeared on the cover of the June 13 issue of Life Magazine in 1949. Torén appeared in 11 American film productions during her brief career. One of her roles was opposite Humphrey Bogart in "Sirocco" (1951), and she also co-starred with Dana Andrews in "Assignment – Paris!" (1952). In 1952, Torén married screenwriter, film director, and producer Leonardo Bercovici, and they had one daughter. She died prematurely from a cerebral hemorrhage, at the age of 31, in 1957.

From 1910 through 1918 Basil Spaulding Millspaugh (1878 - 1960) was a bass-baritone for the Metropolitan Opera Company, before going on Broadway and then radio. His movie debut was in the Marx Brothers' "The Cocoanuts" (1929).

The first U.S. film of Argentinean director Hugo Fregonese, who stayed in Hollywood long enough to churn out a few westerns and genre-pictures.

Mexican Vice Consul Ernesto Romero acted as a Technical Advisor on the film.

Dan Duryea is his usual mean self, and William Conrad is on hand as a fellow thug in this good, but fatalistic noir film that transcends its noir origins. This solid, satisfying vintage 1950 crime drama, B-movie is entertaining from start to finish and well worth a watch if you love film-noir, and recommended for Mason completists.