A month after the outbreak of war, Warsaw is unrecognisable, while Manchester, on the surface, appears very much the same. Will there be a warm welcome home for Harry?

December 1939, and Tom fights for his life on board the HMS Exeter at the Battle of River Plate. Meanwhile, Harry and Lois have a more personal battle to fight.

Harry’s courage is tested at Louvain as he comes face to face with a German sniper, and Kasia’s resistance activity in Warsaw intensifies.

Harry leads his unit on the route to Dunkirk as they fight to make it onto the beach and aboard a ship. Grzegorz and Tom also struggle to survive the chaos of the evacuation.

On a Polish mission as part of the SOE, Harry grasps a second chance at saving Kasia from the horrors of Warsaw, while Lois looks set for happiness with new love, Vernon. Season finale.