In March 1943, Lacey was posted to No. 20 Squadron, Kaylan in India before joining 1572 Gunnery Flight in July of the same year to convert from Blenheims to Hurricanes and then to Republic P-47 Thunderbolts. He stayed in India, being posted to command No. 155 Squadron flying the Spitfire VIII in November 1944 and then as commanding officer of No. 17 Squadron later that month. While based in India, Lacey claimed his last aircraft on 19 February 1945, shooting down a Japanese Army Air Force Nakajima Ki 43 "Oscar" with only nine 20mm cannon rounds.