A Certain Magical Index Season 1 Episode 20

Last Signal (Virus Code)

Accelerator returns to the diner only to find that Last Order has been kidnapped by Ao Amai. Accelerator manages to track down Ao Amai and knocks him out before he can escape with Last Order. However, the virus in Last Order activates earlier than expected and Yoshikawa is still en route with Last Order's incubator. To stop the virus, Accelerator uses his powers and a clean copy of Last Order's data to remove the virus. However, nearing the end of the process, Amai awakens and shoots Accelerator in the head; Accelerator is unable to fully stop the bullet, having chosen to finish removing the virus instead of protecting himself, and collapses afterward. Amai tries to finish him off but is shot by Yoshikawa who has arrived to put Last Order into her incubator. After discussing their roles as researchers and her dream of wanting to become a teacher, she and Amai shoot each other. When Yoshikawa awakens in the hospital, she learns from Heaven Canceller, who is none other than Tōma's frog-faced doctor, that Accelerator saved her but suffers from brain damage from the shot he took while saving Last Order and needs rehabilitation to regain his powers.