The Future Diary - Season 1 Episode 14 Memory Erased

Aru talks to Yuno through her surveillance feed, revealing he dug up three corpses from her garden, two of which had recently had their skulls removed. When he threatens to give this information to the police unless she releases them, the stress causes Yuno to alter her memory again, rendering negotiations moot. As Kousaka uses his cell phone to post his will in his blog, it is apparently turned into a Future Diary by the Eighth diary holder, who adresses him as an "apprentice". On Aru's advice, Kousaka acts out his diary's predictions, reaching an amnesiac Yuno, a catatonic Yuki and a bound Hinata in the control room. His appearance causes Yuki to recover, recalling how Yuno abducted him to keep him safe until July 28th. Yuno places the key to Yuki's shackles on the floor and tosses Kousaka the control panel key, allowing him to free Aru and Mao. Yuno then takes advantage of Kousaka's distraction and shoots at him with a crossbow. However, Yuki, having had his key kicked over to him by Hinata, frees himself and stops Yuno, leaving her behind when his diary predicts the imminent arrival of three diary holders, all apprentices of the Eighth.