Hattori-kun received a letter from Iga's father asking him to take his friends and return home for spring break. Hattori-kun leaves for Iga with his younger brothers Shinzo, Kenichi, Yumeko-chan, and others. However, a suspicious shadow stares at the group... He is a subordinate of the scientific ninja Mechamaro, who has replaced the power of ninjutsu with the power of science. Mechamaro was plotting to confront Hattori-kun in order to prove the strength of scientific ninjas. And in order to occupy Iga no Sato, Hattori-kun sends a fake letter...
| Directing | Hiroshi Sasagawa | Director |
| Production | Shinichi Suzuki | Supervising Producer |
| Visual Effects | Yoshitaka Gokami | Key Animation |
| Visual Effects | Tsukasa Dokite | Key Animation |
| Visual Effects | Tomokazu Kimura | Key Animation |
| Visual Effects | Takayuki Kanouchi | Key Animation |
| Visual Effects | Shiro Okumura | Key Animation |
| Visual Effects | Shinsuke Kasahara | Key Animation |
| Visual Effects | Noriko Gotô | Key Animation |
| Visual Effects | Noboru Takano | Key Animation |
| Visual Effects | Minoru Kibata | Key Animation |
| Visual Effects | Masayoshi Kobayashi | Key Animation |
| Visual Effects | Masaru Sato | Key Animation |
| Visual Effects | Makoto Nakamura | Key Animation |
| Visual Effects | Kiyotsugu Miura | Key Animation |
| Visual Effects | Junichi Hashimoto | Key Animation |
| Visual Effects | Jouji Yanase | Key Animation |
| Visual Effects | Chuji Nakajima | Key Animation |
| Visual Effects | Michiyo Sakurai | Animation Director |
| Art | Takashi Miyano | Art Direction |
| Writing | Shoichiro Okubo | Screenplay |
| Writing | Muneo Kishi | Screenplay |
| Writing | Masaaki Sakurai | Screenplay |