"Operation Infiltrate High School!" is the fifteenth episode of the Blue Jacket series. It first aired in Italy on October 12, 2015, as the sixteenth episode of the broadcast. It aired in Japan on January 15, 2016.
Lupin has stolen the "Cleopatra's Heart", a diamond with a fickle nature that never stays with one owner for long. It lands by chance in the backpack of a high school student, and to retrieve it Lupin goes undercover as "Professor Pierre". But the students are tougher than they seem, and the other teachers seem to be up to something...
- Screenplay: Yuya Takahashi, Ryosuke Fujisawa
- Storyboard: Nobuo Tomizawa
- Production: Keiko Oyamada, Taku Yamada
- Animation direction: Yuya Takahashi, Hiroaki Noguchi
- Animation direction assistants: Nam Hyeonsik, Ryu Hyeonjin
- Chief animation director: Koichi Suenaga