It is the end of the third year of the Great War. The Australian forces are fighting in France and the Middle East, more than two years after the landings at Gallipoli.
In Egypt and Palestine, the young soldiers of the 4th Australian Light Horse Brigade are anxious to prove themselves but frustrated by inaction. The Australian commander of the Desert Mounted Corps, Lieutenant-General Sir Harry Chauvel, is stymied by his British superiors, who have failed to take the Turkish stronghold at Gaza.
The Australian Light Horse patrol the desert, sabotaging the enemy’s train lines and skirmishing with their Bedouin allies. The Light Horse men fight as four-man units, becoming very close-knit.
When trooper Frank (Gary Sweet) is wounded by a Bedouin bullet, his replacement is a raw recruit, Dave Mitchell (Peter Phelps). He joins three seasoned soldiers, Tas (John Walton), Chiller (Tim McKenzie) and an Irishman called Scotty (Jon Blake).
Dave overcomes their hostility by proving he can ride well and shoot straight, but he is completely unnerved by his first action, an ambush of a Turkish mounted column. He is unable to shoot, especially at men who are retreating.
Dave is slightly injured during an attack by a German aeroplane, but he saves the four horses from his unit. In hospital he falls in love with a nurse, Anne (Sigrid Thornton), confiding in her that he fears he is a coward.
Back in the unit, his mates are concerned that he is still unable to fire a shot in anger. Reluctantly, Dave transfers to an ambulance unit.
With the arrival of General Allenby as the new British commander, Lt-Gen Chauvel (Bill Kerr) begins a more offensive role against the Turks. The aim is to take Beersheba, as a prelude to attacking Gaza. The problem is water: the Australian horses will have to go 30 hours without water, and if the attack fails, the horses may die in the desert.
A young British intelligence officer hatches a plan to deceive the enemy. Major Meinertzhagen (Anthony Andrews) concocts a fictitious plan of attack to convince the Turks that the attack on Beersheba is only a diversion.
Instead, 60,000 men attack the small town, beginning with a heavy British artillery barrage early on 31 October 1917. By the end of the day, the attack has had some success, but they are running out of time. The town and its wells must be taken, to get the horses to water.
Chauvel agrees to a desperate plan: two regiments of 4th Light Horse Brigade, the 4th and 12th, will charge across three kilometres of open ground in a frontal attack on Turkish trenches, against artillery and machine guns.
The attack begins in late afternoon, with 500 horses charging at the enemy positions. Against all odds, the attack is successful. The Australians take the town with few casualties.
Tas is killed during the charge and Dave is badly wounded, trying to protect Chiller from a grenade. At El Arish military hospital, Dave is reunited with Anne.
The Australian Light Horse were not true cavalry but mounted infantry. They rode to battle, dismounted, retired the horses to safety and fought as infantry, with rifles instead of lances or swords.
Historians have speculated that one of the reasons that the charge at Beersheba succeeded was that the Germans expected the Australians to dismount and fight on foot. They did not expect a direct charge at Turkish trenches defended by machine guns.
Leading entertainment figures had tipped that Jon Blake would become the next Mel Gibson, when, driving home from the last day of filming on The Lighthorsemen on the night of 1 December 1986, he was critically injured in a road accident.
His car hit a broken-down vehicle parked on the wrong side of the carriageway of the isolated highway in rural South Australia that he was travelling along. An electrical fault had immobilised the other vehicle and the driver pulled over. Having suffered an electrical fault, the car was not illuminated.
Blake received permanent brain damage in the accident. He passed away in May 2011.
Lieutenant-Colonel Murray Bourchier
General Sir Harry Chauvel
Major Richard Meinertzhagen