"Unknown" is a mysterious enemy that suddenly appeared a long time ago. As a countermeasure, the "Evolutionary Railway Development Agency" (ERDA) has developed the "Shinkalion" robot that transform into bullet trains, to prepare for the threat.
"I want to be a cool person who can protect something..." Taisei Oonari, a second-year junior high school student, transfers to Shinkai Gakuen Middle School in search of clues about his older sister who disappeared two years ago.
Just then, the Unknown appears for the first time in 10 years. Taisei happens to have a high aptitude value as a Shinkalion pilot, and is forced to make a decision to fight it. What is the true nature of the Unknown and what is its purpose? What is the truth that comes to light at the end of the fight? The story of the boys' determination and growth begins now.
Megas XLR is a series about an overweight couch potato named Coop who stumbles across a giant robot in a junkyard. He soon discovers that the robot was sent from the future when a woman named Kiva returns to the past to claim what is rightfully hers, though Coop made so many modification to the machine so he's the only one who can fully operate it. Things also heat up when Coop learns that an alien race called the Glorft are also after his MEGAS robot, so he teams up with Kiva and his best friend Jamie to fight them off, though mostly so he can keep his new toy.
Follow the adventures of a group of young cartoon characters who attend the Acme Looniversity to become the next generation of characters from the Looney Tunes series.