Big X

During World War II, Dr. Asagumo is summoned to Nazi Germany by Hitler to assist in developing a powerful new weapon called "Big X." Worried about the consequences of its completion, Dr. Asagumo deliberately slows the project's progress, secretly working with his fellow researcher, the cunning Dr. Engel. Just before Germany's defeat, Dr. Asagumo hides a card containing Big X's secrets inside his son, Shigeru, before being executed by German soldiers. Two decades later, the card is found inside Shigeru, now living in Tokyo. Soon after, a group claiming ties to the Nazis steals the card and finishes the Big X project-revealed to be a drug that allows unlimited bodily expansion. Dr. Engel’s grandson has joined the Nazi Alliance, which now seeks world domination. Shigeru’s son, Akira, takes on the Nazi Alliance and its leader, Hans Engel, fighting to reclaim Big X and stop their plans.