German field marshal Erwin Rommel and his Afrika Korps have driven the British Army back toward Egypt and the vital Suez Canal.

The defending Allied general chooses British Captain MacRoberts to take command of newly arrived, untried Australian troops.

The no-nonsense MacRoberts, disliked by the undisciplined Australians, is surprised to see in their ranks his former schoolmaster, Tom Bartlett, an alcoholic dismissed from education for drunkenness.

Under cover of a sandstorm, Rommel's tanks and infantry attack where the Allied general predicted and head directly at MacRoberts' men.

The film is based on the Australian 9th Division, who were charged with the defence of Tobruk under the command of General Leslie Morshead.

Morshead was a distinguished Australian citizen-soldier, but is depicted in the film as the anonymous "General" and played by English actor Robert Douglas.

It was, reportedly, partly made to portray a less likeable General Rommel, after criticism that film had been too friendly to the Germans.

In July 1952 Fox announced that filming would take place in September and the three leads would be played by Michael Rennie, Robert Newton and James Robertson Justice.

[8][9] The script was written by an American, Richard Murphy, who was familiar with Australian servicemen from his time being a liaison officer with the Ninth Division in New Guinea, after its withdrawal from the Middle East in 1942.

[12] Several genuine Australian actors were cast, including Chips Rafferty, Charles Tingwell, Michael Pate and John O'Malley.

Australian journalist Alan Moorehead was used as a consultant and the technical adviser was an Englishman now in the Canadian Army, Lieutenant Adrian (George) Acland, who took part in the defence of Tobruk.

The title of the film is a misnomer: The "Desert Rats" were actually the British 7th Armoured Division, the name coming from their jerboa shoulder flash.

"But whenever difficulties of that sort were mentioned the Hollywood experts claimed to be working on a script based on the actual battle plans of the campaign.

Lieutenant-General Sir Leslie Morshead said that, "The story is wholly foreign to the Tobruk I knew, and to its force which comprised almost as many gallant, purposeful British troops as those of the Ninth Division, all of whom I had the honour to command.