While human fleets continue to battle the remaining Kafer warships along the frontier, a tiny unnamed star system serves as the home of a forward base for Kafer warships which continue to conduct raids deep into the French Arm. The system, known simply as DM +36 2393, contains a single garden world the German colony world of Dunkelheim. This is the location of the Kafers' citadel base and the target of Operation Overlord.The year is 2303. The Kafer invasion has been halted and the alien warships have been pushed back to the frontier. Still, the fighting is far from over. Pockets of Kafer ground troops exist on every single human colony world from Beowulf to Aurore. Kafer guerillas continue to attack the colonial towns and cities. Numerous Kafer warships continue to operate within the French Arm, raiding colonies, attacking unprotected shipping, and ambushing stray warships. However, these raiders have a weak link they need to be supplied. Their forward base at Dunkelheim has to be eliminated and Admiral Borodin has put the Americans to the task.Operation Overlord is the American Marine assault on the Kafer citadel based at Dunkelheim. The adventure follows a group of American Marines from their interface assault landing through a mission which takes them into the heart of the Kafer "Ch*!!" This book contains information on the colony world of Dunkelheim and the citadel which serves as the Kafer "Safe Place." This book also contains extensive information about the American Marines, their equipment and their organization.A modified skills list is even included for characters who enter the career path of the Corps. Finally, a brief update on the Kafer War is provided, describing the disposition of naval forces and of the American Marines following the completion of the adventure.Operation Overlord serves as more than just an adventure. Its completion leaves plenty of room for further adventures, allowing directors to easily stage a campaign against the Kafers on post-invasion Dunkelheim.