Rust Never Sleeps

In the Technodrome, Krang works on an oxidizer rocket with enough power to blast the Technodrome to Earth. But something goes wrong, and instead of "thrust", the device grows "rust"! Shredder berates Krang for yet another failed idea, but Krang sees this as a tool of conquest, by threatening to rust all metal on the Earth unless the citizens surrender. Meanwhile, the Turtles are in Paris with Splinter, who is showing them the sights via the sewer system. Shredder, Bebop and Rocksteady arrive in Paris with the device, which they charge with Paris' electrical power system. April arrives to cover the story of mysterious power failures in the City of Lights, and gets captured by Shredder. The Turtles head for the rescue as Rocksteady and Bebop blast everything in sight with their rust encruster. They stop the rusting as the Eiffel Tower itself begins to collapse from rust. The Turtles rescue April and just in time, Donatello reverses the rust encruster and saves the Eiffel Tower.

Michelangelo, Leonardo, Raphael, Donatello, Splinter, April O'Neil, Shredder, Krang, Burne Thompson, Vernon

Part of a "Vacation in Europe" mini-series, which takes place right from where "Plan Six From Outer Space" left off.

A Season 4 episode but it aired during the seventh year of production.