Splinter, Shredder and the weapons collector Lafayette Le Drone all see a TV report about the famed Sword of Yurikawa being on display at the Japanese embassy. Shredder immediately wants to steal it for use in his and Krang's newest scheme, while La Drone wants to add it to his collection. Splinter, on the other hand, orders the Turtles to go guard it.
On the way to the Japanese embassy, however, the Turtles stop for pizza. While they are eating, three mysterious ninjas sneak into the embassy. The first replaces the real sword with a copy, the second punches out the camera and replaces the first fake with a second, and the third just steals the second fake.
Upon learning of the theft, the remorseful Turtles immediately set about tracking down the thief, and briefly encounter the person who stole the real sword. La Drone and Shredder soon discover that their swords are fakes.
The mysterious ninja appears again and challenges the Turtles, displaying the sword's power. But when asked to hand it over, he politely does so and disappears.
The Turtles are captured by Shredder, who plans to use the sword to cut down a bridge and cause toxic waste to flood into the muddy river below, creating a mud mutant army. He also plans to drown the Turtles at the same time. He transforms the sword into a chainsaw, only to have it suddenly float out of his hands and start attacking him. La Drone tries to handle it, only to have it grow enormous and chase him back into his tank.
The mysterious ninja reappears and uses the sword to rescue the Turtles, only to reveal himself as Splinter. He then uses the sword to repair the broken bridge, saying that the sword cannot be used for evil. Afterwards, the Turtles are charged with returning the blade to the Embassy.
- Leonardo (Cam Clarke)
- Donatello (Barry Gordon)
- Michelangelo (Townsend Coleman)
- Raphael (Rob Paulsen)
- Splinter (Peter Renaday)
- April O'Neil (Renae Jacobs)
- Shredder (James Avery)
- Bebop (Barry Gordon)
- Rocksteady (Cam Clarke)
- Krang (Pat Fraley)
- Lafayette Le Drone (Rob Paulsen)
- Ambassador Murishima (Pat Fraley)
- Police Chief (Townsend Coleman)
- Turtle Lair
- Lafayette Le Drone's mansion
- City streets
- Tri-State Bridge
- Japanese Embassy to the USA
- Transport Module
- LeDrone's armored tank
Home media releases
- Teenage Mutant Ninja Turtles Season 6
- Teenage Mutant Ninja Turtles: The Complete Classic Series Collection
- When the Turtles mock Leonardo after he enthusiastically tells them they need to get into the ninja spirit and go keep guard of the sword, Leonardo's mouth is seen moving along with all the other Turtles, as if he's also taking part in mocking himself.
- Leonardo has Michelangelo's colors when he remarks that Splinter is the only one who can control the sword.
- Shredder removes the grate when he enters the Japanese Embassy, but the grate is seen back on the wall when he jumps to the ground.
- The video footage of LeDrone stealing the "sword" shows him taking out the surveillance camera with a blast from his power ring when he really smashes the camera with his fist.
- When Splinter uses the sword's power to turn Raphael's sai red hot, the top of the weapon's handle retains its normal color.
- Splinter tells the Turtles that there would be dire consequences if the Sword of Yurikawa fell into evil hands, but later at the end he tells them that the sword can only be use for good as to why it turned against Shredder and Le Drone.
- Yurikawa is also the name of Saki Yurikawa, the infamous serial killer from the horror manga series Reiko the Zombie Shop.
- The Sword of Yurikawa is very much similar to the Sword of Tengu from the 2003 series, in that it is a magical blade coveted by Shredder. In some other ways it is rather different, since it also possesses transformation powers and seemingly a will of its own.