This Sceptred Isle (2018)

The world is at war. An ongoing conflict between Russia and NATO has caused civil unrest in the UK. As martial law decends upon the country, groups of militia start to fight back. A small squad of soldiers, cut off from their own lines, must trek back to safety. While under conflicting orders from the battle hardened Sergeant Major Sandford, and their NATO liasion, Lieutenant Kowalski, the men must ultimately choose who to follow - and who should die.