The universe's very existence is threatened by a galactic anomaly called the Grand Black Hole. Created from the destruction of Unicron, the black hole is devouring every single planet in its path, and its next target is Cybertron. The Cybertronians attempt in vain to stop the Black Hole and are forced to abandon their home world and evacuate to Earth.
They also meet an ancient Autobot named Vector Prime who says the only hope of stopping the Black Hole and saving the universe is to find the four Cyber Planet Keys. Optimus Prime (Galaxy Convoy) and his team of Autobots set up base on Earth with the help of three human children named Coby, Bud and Lori, who help them properly disguise themselves from humans and adapt to life on Earth.
However, the power-hungry Decepticon leader known as Megatron (Master Megatron) is also after the Planet Keys to use for his own evil ambitions. The hunt takes them to various worlds where they encounter other Transformers in their search. In their mission, both sides make new allies and enemies on the way. Will Optimus Prime and the Autobots find the keys? Or will the universe face certain annihilation?
Note: It is debatable on whether or not Cybertron is a continuation of the previous two shows Transformers shows, Armada and Energon. Galaxy Force (the Japanese version) definitely takes place in its own separate universe, and the Dub seems to do little to connect to Armada and Energon.
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