The opening four episodes of the Japanese sci-fi anime series. Since World War II, mankind has been fighting to defend itself from an invasion by alien forces. To ensure the future of the human race, the Japanese government is compulsorily recruiting high school students to become HWT pilots, including the 5121st Platoon, which has just added a mysterious girl named Mai Shibamura to its ranks. Episodes are: 'The Visitor', 'Going My Way', 'Fire Works' and 'Duelist'.