The opening blitz is pure adrenaline: orchestral war movie energy, witches screaming through the sky on striker units, the Neuroi obliterating everything in their path. You get the full world explained in minutes, weapons and strategy crystal clear, no throat-clearing. One episode of setup that burns hotter than most pilots twice its length.
Extraterrestrial invaders called the Neuroi descend on Earth during the 1940s, leaving civilization in ruins. Conventional weapons cannot harm them, so humanity turns to Striker Units: mechanical leg devices that amplify magic and let their wearers fly. Young witches from many nations band together to fight back as the Strike Witches. The man who led the Striker Unit's creation is believed to have died in service. His daughter lives a fairly ordinary life, though she holds strong, untrained magical power that she hopes to use for healing one day. Then she is suddenly swept into a search to learn whether her father survived, and she comes face to face with his invention and the chance to use it herself. Made as a concept OVA for the later 2008 TV series, it mixes action, ecchi and sci-fi.