Australia's only fully war-time feature, The Rats of Tobruk focuses on three friends who are cattle droving in the outback just before the outbreak of World War II. By 1941, restless Bluey Donkin, easy-going Milo Trent, and Shakespeare-quoting Englishman Peter Linton have decided to join the Australian Imperial Forces (A.I.F.) and later find themselves in North Africa fighting Rommel's army.
After early successes against the Italian army, the Australian 9th Division finds itself besieged in Tobruk. When not fighting, the men have comic encounters with a barber, while Peter falls for a nurse, Sister Mary, after being wounded. The other two men are also later wounded, but it is Peter who is eventually killed just before the others are able to repel the enemy. Bluey and Milo are then later transferred to New Guinea, where Bluey is injured and Milo killed by a sniper. Bluey manages to kill the sniper.
A romance subplot occurs between Bluey (who prior to leaving Australia was not prepared to settle down with any woman) and the daughter of a squatter, Kate, who is in love with him. When Bluey finally returns home, he and Kate are united.
