On 1 September 1918 in the attack on Péronne, France, Currey, as a 22-year-old private in the 53rd Battalion, rushed forward under heavy machine-gun fire and captured single-handed a 77-mm field gun which had been holding up the advance, killing all the crew. Later, when the advance was checked by an enemy strong-point he crept round the flank and engaged the post with a Lewis gun, then rushed it, causing many casualties. Subsequently he volunteered to carry orders for withdrawal to an isolated company, bringing back valuable information, doing so under heavy fire and despite being gassed. The citation published in the "London Gazette" of 14 December 1918 concluded that his behaviour was a "striking example of coolness, determination and utter disregard of danger... and his gallant work contributed largely to the success of the operation."