In 1939 the alien Neuroi appear without warning and overrun most of Europe. Humanity answers with Striker Units, flying gear that only Witches, girls with magic, can use. On the eastern front, the Allied Forces' 502nd Joint Fighter Wing, the Brave Witches, prepare for operations from their base in Petersburg, in the Empire of Orussia. When one member is badly hurt on the way to headquarters, her sister Hikari Karibuchi steps in to replace her. Hikari has no special abilities and little magical power, yet she is set on proving to her new comrades that she deserves to be called a Witch. A spin-off of Strike Witches, the show mixes aerial sci-fi action with ecchi elements.