Bleach: Season 11, Episode 209
This episode is set nine years after the previous one. The 9th squad are sent to investigate after people begin to vanish from Rukongai. Whilst out on patrol Captain Kensei Mugurumathey saves a young boy from a hollow, his name is Shuhei Hisagi. He then discovers that 10 of his own men have also vanished and calls for the Technological Research Bureau to help in the investigation. As such Hiyori is dispatched.