Devastation / Doomsday

A terrible virus wipes out 90% of the inhabitants of Scotland. To stem the epidemic, the English government builds an impenetrable wall. Scotland is now a barbaric and violent no man's land where the survivors are cut off from the world.
When 30 years later, the same virus reappears in the heart of London, a shock commando goes on a suicide mission to search for a possible vaccine in a Scotland controlled by rival gangs...