Injured in the Liverpool Blitz, he joined the RAF Film Unit, where he worked as camera operator on propaganda films for the Ministry of Information and the British Council. We Serve (1942), a recruiting film for women, was directed by Carol Reed, who made Annakin his assistant Director, after which Annakin directed several training films for Verity Films, a group led by Sydney Box, who was about to become head of Gainsborough Pictures. His early documentaries included London 1942 (1942), Make Fruitful the Land (1945), We of the West Riding (1945), and English Criminal Justice (1946). He also made the shorts It Began on the Clyde (1946) and Fenlands (1946).