In the very beginning of the episode we see a flashback of Suzu's past. Suzu's brother was killed by the Shinsengumi and Yoshida took Suzu in as his page.
Hijikata sent Tatsunosuke and Tetsunosuke to Hyogo to pick up a parcel for him, on their way to the Yodo River, Tetsunosuke saw Suzu and started chasing after him. Suzu saw him coming and started running until they both got lost. They're finally able to find their way to Yodo river and met up with the worried sick Tatsunosuke.
After crossing the river, Tetsunosuke met a mysterious person who sang a strange song (US national anthem) in a strange language (English), the same strange language that his father spoke. Tetsunosuke ran after this person, but he wasn't the only one. Four roshis were after this person and took Tetsunosuke hostage. The mysterious person not only carries a katana, but also carries a pistol. After the roshis ran away, Tetsunosuke wanted to ask this person some questions, but he doesn't want to reveal his secret.
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