Todd enlisted soon after the outbreak of the Second World War, entering the Royal Military College, Sandhurst in late 1940. On 29 January 1941, he was one of 26 cadets injured when 'D' Block of New College was hit by a German bomb in an attack by the Luftwaffe. In his memoirs, he describes seeing the bomb pass through the ceiling in front of him before he was blown out of the building by its blast, landing on a grass bank and suffering multiple lacerations, five cadets were killed in the incident. Todd passed out in the spring of 1941. On the day he received his commission, he tried to join several friends at the Café de Paris in London, but could not get a table booked for the evening. That evening, the venue was destroyed in an air raid, and 15 newly commissioned subalterns were killed.