Set in the future on a war-ravaged Earth, four exhausted soldiers man Sentinel - a remote military base in a vast ocean that separates two warring continents. While their tour of duty ended three months ago, the relief crew still hasn't arrived and as the empty weeks turn to months, paranoia descends, testing relationships to breaking point...

In the North African desert at the height of WWII, an SAS raiding squad led by Lt. David Walker and Sgt. Daniel Thomas capture an Afrika Korps soldier, Cpl. Ulf Steiner, whose unit was taken out by an unseen enemy.