Ep 7. Osoroshi No Tabi

The episode "Osoroshi No Tabi" of Teenage Mutant Ninja Turtles (2012) season 5 takes the turtles on a journey back in time to feudal Japan. The turtles find themselves in a monastery where they meet the mystical Hamato Yoshi, the original owner of Leonardo's katana. They learn that Yoshi has been meditating for centuries while waiting for his true love, Tang Shen, to return to him.

As the turtles try to find a way to return to their own time, they are encountered by the evil Kavaxas, who has been awakened by Oroku Saki (aka the Shredder) in the present day. Kavaxas seeks to unleash his own brand of chaos upon the world, and the turtles must stop him before he can wreak havoc on both the past and present.

Meanwhile, in the present day, the rest of the team must cope with the sudden reappearance of the villainous Karai, who has been missing since the end of season 4. Karai's return is a complicated one, however, as she appears to be suffering from amnesia and has no recollection of her past with the turtles.

As the two storylines play out, the turtles must juggle their responsibilities in both the past and present, all while trying to prevent Kavaxas from carrying out his nefarious plan. Along the way, they must also confront their own personal demons and come to terms with the fact that the actions of their past selves have far-reaching consequences that still affect the world today.

With plenty of action, humor, and heart, "Osoroshi No Tabi" is a standout episode in the series that showcases the show's ability to seamlessly blend different genres and timelines into a cohesive and entertaining narrative.