Hughes rejoined the army in November 1939, two months after the Second World War began, and soon became Commanding officer (CO) of the 1/6th Battalion, Queen's, another TA unit, then serving as part of the 131st Infantry Brigade of the 44th (Home Counties) Infantry Division, then commanded by Major General Edmund Osborne. After several months of training in Dorset, the battalion was sent overseas to France, arriving there in early April 1940 where it became part of the British Expeditionary Force (BEF). Only a few weeks later the German Army launched its attack in the West, and the battalion moved up to the River Escaut and was ordered to hold the line there. The Germans attacked in force and Hughes' battalion met them and were, for 36 hours, engaged in severe fighting, which resulted in the Germans breaking through on the battalion's flanks, forcing Hughes to order his battalion to retreat to avoid complete encirclement. The greatly depleted battalion eventually, along with most of the rest of the BEF, made their way back to Dunkirk, and were subsequently evacuated to England. Hughes, for his leadership of the battalion in France, was awarded the Distinguished Service Order (DSO).