KaylaBunBun
For 10,000 years, the evil Galra Empire led by Emperor Zarkon has plagued the universe by destroying and enslaving entire civilizations. The only known threat strong enough to stand against the Empire is the legendary "Defender of the Universe" Voltron, a 100-meter tall robot warrior composed of six robot Lions whose pilots are known as the Paladins of Voltron. The sixth, however, is a very important piece. It acts as Voltron's protector, and the pilot acts as a shield to the other pilots.
Unfortunately, the mighty robot was separated long ago by the king of planet Altea, Alfor, in order to prevent its power from falling into the hands of Zarkon. King Alfor connected the six Lions to the life force of his daughter, Princess Allura, and hid them across the universe at different locations. Princess Allura and her advisor Coran were hidden on planet Arus along with the Black Lion, placed in a deep sleep within the Castle of Lions in hopes that Alfor could return to awaken them, but the king was slain by Zarkon.
In the present, the Galra Empire's path of conquest and search for Voltron leads them to Earth's solar system where they take a crew of space explorers captive. A year later, one of the crew members, Shiro, escapes imprisonment and returns to Earth with warning of the alien threat. A group of space cadets - Lance, Hunk, Pidge, Keith, and Corinne - help Shiro discover the Blue Lion hidden away on Earth, sweeping the group up into the ancient war. They awaken Princess Allura, reunite the six Lions as the new Paladins to form Voltron, the sixth immediately going back to being a protector, and fight to defeat the entire Galra Empire.