To counter terrorist attacks by machine beasts threatening the world, Dr. Yajima advances development of a humanoid giant robot called "Machine Lady." However, the robot's main computer—its central component—employs a unique system requiring perfect synchronization with the pilot's brain to activate. As a result, when the pilot faces enemy attacks, the damage received is fed back directly into their brain, causing intense pain and posing extreme risks. Amid these dangers, Megumi Asakura, a top operative of the Earth Defense Force, is chosen as the sole pilot. Her selection reflects both her proven battlefield excellence and her willingness to face this perilous system. Yet behind this choice lie unforeseen events and decisions, harboring the possibility of a "BAD END" fate.