While cruising around Dimension X, the Nutrinos decide to 'buzz' the Technodrome. However, when they fly by, they notice that a cargo bay door is open and can't resist the temptation. Inside, they tap into a transmission between Krang and Shredder on Earth. Through this transmission, the Nutrinos learn of Krang/Shredder's latest plan to destroy the Turtles. The Nutrinos decide that they can't sit idly by and watch, so they open their own portal and arrive on Earth to warn the Turtles. (thetvdb.com)