Nagisa's Time

Knife in hand and consumed by fury, Nagisa vows to kill Takaoka, but Terasaka hurls his stun rod to jolt the boy out of his bloodlust. He warns Nagisa not to throw away the real target, Korosensei, by getting himself jailed, then buckles under the poison. Steadied, Nagisa strips off his jacket, pockets the stun rod, and accepts the fight after Takaoka admits he carries three spare vials, too few to treat every stricken student yet the only hope available.

The former soldier's sharp reflexes leave Nagisa no opening, and the boy takes a savage beating. Korosensei readies Karasuma to step in, but Terasaka insists it will not be needed. Recalling the trick Lovro taught him before the island trip, Nagisa fixes Takaoka's gaze on his blade, lets it fall, and follows the distraction with a sudden loud clap. In that frozen moment he closes the distance and drops Takaoka with the stun rod, thanking him with a chilling smile before finishing the job.

The class celebrates, though the sparse antidote still cannot save everyone. Gastro, Grip, and Smog arrive, freed of their contract now that their employer is beaten. They reveal a hidden kindness: when Takaoka confessed he never meant to hand over the real cure, the trio swapped the genuine pathogen for a harmless one to protect their reputations without murdering children. Smog passes over the medicine for the fake virus, Karasuma has the hitmen and Takaoka carried off, and the group heads back to the hotel, where the sick friends recover overnight.

Rested at last, the students watch Korosensei entombed beneath anti-sensei pellets and concrete. When the twenty-four hours end, the shell bursts apart and their teacher lands behind them in his usual form. The class enjoys the rest of the resort trip before returning to Kunugigaoka to begin their second semester of assassination.

This is the final episode of season one and covers chapters 71 through 73. Earlier episodes borrowed their titles from matching manga chapters, but the chapter actually named Nagisa's Time appears far later in the source material. The anime also skips Takaoka's military interrogation, which the manga includes. It aired in Japan on June 19, 2015, with the dub on July 22, 2015.