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.
Shingo Katori
Soichiro Kanzaki
Miki Sakai
Noriko Kinoshita
Anne Suzuki
Misaki Kinoshita
Yuya Endo
Yusuke Sakamoto
Kyôtaro Shimizu
Hidetaka Ono
Yuki
Toshiya Matsuoka
Katsumi Takahashi
Yusuke's Father
Kuniko Asagi
Yusuke's Mother
