610 (County of Chester) Squadron was formed in February 1936 as a bomber squadron. With personnel recruited from the local area for the expanding Auxiliary Air Force, these `weekend fliers' were moulded into a cohesive fighting unit at Hooton Park, Cheshire. However, as the Second World War loomed, 610 Squadron transferred to Fighter Command, ultimately operating the iconic Supermarine Spitfire. Flying from Gravesend, 610 Squadron suffered seven pilots killed and one wounded whilst desperately protecting the Dunkirk evacuation. The Squadron then played a key role in the Battle of Britain, claiming a heavy toll on the Luftwaffe whilst operating from Biggin Hill and Hawkinge. After further tragic losses, 610's veterans moved to Acklington, Northumberland, to train replacement pilots. Despite the famous photographs of its men and aircraft during 1940, 610's valiant history remains largely unknown. This detailed book recounts their heroic story for the first time, combining the Operations Record Book with Combat Reports, pilots' Log Books, ground crew and relatives' testimonies, plus a rare interview with Wing Commander Brian Smith, a founding Squadron member who fought during 1940. Finally, this fascinating story is brought to life with many unpublished photographs from the Squadron's Association, to recognise 610 Squadron's brave sacrifice.