11-year-old Yusuke and his classmates camp in the woods and see a strange light. They discover a small metallic object like a robot which talks, calls himself Tetra and knows Yusuke's name. Tetra can create wonderful gadgets but actually has to save the world with Yusuke's help from extraterrestrials with bad intentions.
as Soichiro Kanzaki
as Noriko Kinoshita
as Misaki Kinoshita
as Yusuke Sakamoto
as Hidetaka Ono
as Toshiya Matsuoka
as Yusuke's Father
as Yusuke's Mother
as Misawa
as Female Researcher / Voice of Tetra
as Snack Shop Lady
as Man
as Agent B
as Misaki Kinoshita, 20 years later
as Byoid (voice)
as Agent A
as Yusuke Sakamoto, 20 years later
as Toshiya Matsuoka, 20 years later
as Hidetaka Ono, 20 years later
