In the midst of Earth's turmoil caused by an alien threat called the 'Neuroi' during the 1940s, humanity faces widespread devastation. Amidst this chaos, a man spearheads the creation of the 'Striker unit,' a weapon that harnesses magical abilities and grants flight through specialized leg gear resembling witches' brooms. Assembling young witches worldwide, known as Strike Witches, they unite to combat the Neuroi menace. Despite the belief that the inventor perished in action, his daughter leads a mundane existence, harboring immense untapped magical potential geared towards healing. Unexpectedly, she embarks on a quest to uncover the truth about her father's fate. Along this journey, she stumbles upon his remarkable creation, contemplating the prospect of wielding its power herself.