In 1937 he entered University College, London as a medical student. When World War II broke out in 1939, he was sent to France as part of the British Expeditionary Force, attached to intelligence and in charge of a small mobile laboratory and an assistant to look for secret writing in Army mail. When the Expeditionary Force began to retreat towards Dunkirk, he became a dispatch rider assigned a small car. He was one of the last to arrive in Dunkirk for the evacuation, driving a general there under frequent attacks from German planes.