The earlier film was directed and written by Walter Summers and is based on the same novel. The Lost Patrol stars Victor McLaglen, Boris Karloff, Wallace Ford, Reginald Denny, J. M. Kerrigan and Alan Hale.
During World War I, the young lieutenant in charge of a small British mounted patrol in the empty Mesopotamian desert is shot and killed by an unseen sniper. This leaves the sergeant at a loss, since he had not been told what their mission is and has no idea where they are. Riding north in the hope of rejoining their brigade, the eleven remaining men reach a deserted oasis where they find water, dates to eat and shelter.
During the night, one of the sentries is killed, the other seriously wounded, and all their horses are stolen, leaving them stranded. One by one, the remaining men are picked off by the unseen assailants. In desperation, the sergeant sends two men chosen by lot on foot for help, but they are caught and their mutilated bodies returned. One man, Abelson, suffering from heat exhaustion, sees a mirage and wanders into deadly rifle fire. The pilot of a British biplane spots the survivors, but nonchalantly lands nearby and despite frantic warnings is killed. After dark, the sergeant takes the machine gun from the aircraft and then sets the plane on fire as a signal to any British troops. Sanders, a religious fanatic, goes mad and walks into deadly fire.
In the end only the sergeant is left and, thinking he too is dead, the six Arabs who have been besieging the oasis advance on foot. Using the machine gun from the aircraft, he kills them all. A British patrol which had seen the smoke from the burning plane rides up and the officer in charge asks the sergeant roughly where his men are. In silence, the sergeant shows him their graves.
The film was directed by John Ford, who directed The World Moves On and Judge Priest in the year it came out. Ford co-produced the film along with Merian C. Cooper and Cliff Reid. Cooper himself had a military career. He served in the United States Army Air Service from 1916 to 1921, and would return to military service in World War II, in which he served from 1941 to 1945, reaching the rank of brigadier general. Ford himself served in the United States Navy in World War II from 1942 to 1945, reaching the rank of commander. He stayed on the reserve from 1946 to 1962. On the reserve, Ford reached the rank of rear admiral. The script was written by Dudley Nichols and Garrett Fort, which was based on the 1927 war novel Patrol, by Philip MacDonald. The novel was first adapted in 1929, by Walter Summers, who directed and wrote the film with Victor McLaglen’s younger brother Cyril in the lead role. The novel and movies focus on the psychological strain on a patrol of British soldiers when they become lost in the desert and surrounded by the enemy in Iraq. MacDonald himself served in the British cavalry during World War I in the Mesopotamian campaign.
Richard Dix was cast to play the lead role in The Lost Patrol but he went into another film instead and Victor McLaglen replaced him. McLaglen himself was a World War I veteran, having served as a Captain (acting) with the 10th Battalion, Middlesex Regiment, part of the Princess of Wales's Royal Regiment (Queen's and Royal Hampshires). Later he claimed to have served with the Royal Irish Fusiliers. He served for a time as military Assistant Provost Marshal for the city of Baghdad. McLaglen would work with Ford and Nichols again in The Informer. The three of them would win Academy Awards for Best Actor, Best Director and Best Adapted Screenplay.
Boris Karloff, known for his role as Frankenstein's monster in Frankenstein (1931), Bride of Frankenstein (1935) and Son of Frankenstein (1939), was cast as Sanders, the religious doctor of the patrol. Already an actor in 1909, Karloff attempted to enlist in the British Army during World War I, but was rejected due to his heart murmur.
Wallace Ford and Reginald Denny, who played Morelli and Brown, had both served in World War I. Ford served in the United States cavalry, while Denny served as an observer/gunner in the Royal Flying Corps. Denny would eventually found a company that made radio-controlled target aircraft during World War II.
The other seven members of the British patrol were played by J. M. Kerrigan, Billy Bevan, Alan Hale, Brandon Hurst, Douglas Walton, Sammy Stein and Paul Hanson. The pilot of the British plane who spots the survivors of the patrol was played by Howard Wilson. The Arabs were played by Abdullah Abbas, Frank Baker (who played the rescue patrol colonel) and Francis Ford (John Ford’s older brother). Neville Clark played Lieutenant Hawkins, the commanding officer of the British patrol, who gets killed by an unseen Arab soldier in the beginning of the film.
The Lost Patrol was filmed in Algodones Dunes, California and Yuma, Arizona. Filming began in August 31 and ended in September 22, 1933. In Algodones Dones, the temperatures soared and one of the film's producers wound up in the hospital with sunstroke. According to Karloff’s biographer Peter Underwood, the temperature on the Yuma locations could be as hot as 150 degrees and actors were limited to working two hours a day.
Film historian Alun Evans in Brassey's Guide to War Films, considered the production, "... something of a classic, if only for the number of copy-cat pictures it spawned." The film made a profit of $84,000. Film reviewer Paul Tatara claims, "Critics have alternately hailed The Lost Patrol as a flawed masterpiece and a failed experiment. In reality, it's probably a little bit of both." In a contemporary review, Mourdant Hall of The New York Times, noted: "In The Lost Patrol, a picture now sojourning at the Rialto, women are conspicuous by their absence. (Because the story didn't call for any woman....a war story only involving men)It is an audible adaptation of Philip MacDonald's novel Patrol, which was exhibited here in silent film form several years ago. The present production is highly effective from a photographic standpoint, but the incidents are often strained."
Among the awards for The Lost Patrol, it was listed as one of the "10 Best Films - 1934" by The New York Times and received nominations for Best Picture in the 1934 National Board of Review and for Max Steiner for the 1934 Academy of Motion Picture Arts and Sciences Academy Award for Original Music Score.