Set during World War I, the film tells the story of the 1st Australian Tunnelling Company's efforts in mining underneath Hill 60 in the Ypres Salient on the Western Front.

During the war, a series of mines filled with explosive charges were placed beneath German lines to aid the advance of British troops.

He has the opportunity to do so when the British Army forms the 1st Australian Tunnelling Company to supplement the Royal Engineers; Woodward is commissioned to lead the unit.

In May 1916, near Armentières, France, 30 feet below the Western Front, Woodward meets Frank Tiffin, a young Australian soldier who is suffering from shell shock.

Woodward is later tasked with destroying the Red House, a fortified German position raining enfilade fire down upon the frontmost section of the British trenches.

Although Woodward initially proposed tunneling beneath the Red House, his commanding officer, Colonel Wilson Rutledge, insisted that it be done by dawn.

Upon their arrival, Tiffin, Walter Sneddon and Billy Bacon are separated from the rest of the battalion and pinned down by German machine gun fire.

During an inspection, it is revealed that the Canadian & British Engineers have been tunneling deep below the Messines Ridge (helling van Mesen - heuvelrug Wijtschate-Mesen) for months, planting a million pounds of ammonium nitrate in 21 massive mine chambers.

Woodward is tasked with maintaining two of the mines dug by the Canadians, Hill 60 and The Caterpillar, as the British military buildup begins; they hope to kill as many German troops as possible.

[5] The majority of the war scenes were written to take place inside the tunnels so a tense environment could be achieved while facilitating the film's tight budget.

Impressed with the intensity of the film's claustrophobic action, Leimbach approached Sims, who agreed to direct Beneath Hill 60 after reading an early treatment.

[5] Actor Hugo Weaving showed interest in participating in the film and was offered the role of Oliver Woodward, but ultimately declined due to his claustrophobia.