MacCarthy was born in 1913 in the town of Castletownbere, Beara Peninsula County Cork, Ireland. His parents owned land and businesses in the area. He attended Clongowes Wood School and University College Cork. He graduated with a medical degree in 1938. Lacking family connections, he was unable to obtain employment as a doctor in Ireland so he moved to the United Kingdom, working first in Wales, then in London. There, he met two former classmates from his medical school and, after a night of drinking with them, decided to join the British armed forces as a medical officer. Which service was decided for him by a coin toss made by a nightclub hostess in the early hours of the morning.
RAF career
In 1940, he was posted to France and was evacuated from Dunkirk where he attended wounded Allied soldiers while under fire from German aircraft. In September 1940, he was promoted to flight lieutenant. The following year he was awarded the George Medal for his part in the rescue of the crew of a crashed and burning Wellington bomber at RAF Honington. The aircraft had crash landed after its undercarriage had failed to lower and it came to rest on the airfields bomb dump, where it caught fire. Together with Group Captain John Astley Gray, MacCarthy entered the burning wreck and rescued two crewmen, but were unable to save the pilot. Gray was badly burned during the rescue; MacCarthy was also burned, but less seriously. Posted to the Far East in 1941, MacCarthy was captured by the Japanese in Sumatra. The prison ship transporting Allied prisoners to Japan was sunk by a US submarine. MacCarthy had to do the best he could for his patients whilst splashing around in the South China Sea. After being initial rescued by a Japanese Destroyer the crew then started to throw rescued prisoners overboard and the remaining prisoners on the destroyer jumped back into the ocean and clambered back on the wreckage. A Japanese fishing boat pulled him out of the ocean and transported him to Japan. There, he cared for Allied prisoners of war who were forced to work in horrific conditions. To the Japanese ear 'MacCarthy' and 'MacArthur' were indistinguishable. The Japanese assumed that MacCarthy must be a close blood relative of the American commander. Therefore, whenever MacCarthy answered his name, he was struck on the forehead. This may have contributed to his developing a brain clot in later life. He was in charge of a working party in Nagasaki when the atomic bomb was dropped on that city on 9 August 1945. The prisoners had previously been warned, by secret radio, to take cover at a particular time of day without being given any further details. When the war ended, when some Australian ex-prisoners were attempting to lynch their Japanese captors, MacCarthy locked the Japanese guards in a cell and threw the key into the sea. MacCarthy was the senior Allied serviceman in Japan at the Japanese surrender. In 1946, MacCarthy was appointed an Officer of the Order of the British Empire. In 1948, he was promoted to substantive rank of squadron leader, having held the rank of acting squadron leader since 1940.
Later years
MacCarthy later practiced medicine in southern England. In 1979 he published an account of his wartime ordeal, titled A Doctor's War. He died in Northwood, London on 11 October 1995. In July 2017, Buckingham Palace announced that Prince Harry will formally name a new RAF medical centre at RAF Honington in his honour.
