After service on the Eastern front he decides to become an officer to protect his family at home from persecution by the NSDAP. On recovering from a severe wounding he is sent to Normandy and made temporary commander of the Merville gun battery as a second lieutenant aged 24. No more senior replacement arrives and he finds himself in command of the Battery on D-Day, 6th June 1944.
From the 6th June until 17th August 1944 he holds a key position as the foremost German artillery unit commander against British invaders, ably supported by his battery Sergeant Major.
The majority of the story consists of verbatim accounts by German and British servicemen.