I Am Groot
Sentient and ambulatory plant-being Groot left his Flora colossus people behind on their native Planet X to travel out into the galaxy. Both before and after meeting the genetically enhanced creature known as Rocket, Groot racked up an impressive list of criminal charges from the Nova Corps police force while working for crime lords in various capacities.
Together, Groot and Rocket finally concentrated on being bounty hunters, a job that took them to many exotic worlds. Upon tracking Peter Quill, AKA Star-Lord, to Xandar for the bounty on his head, Groot and Rocket ran afoul of the assassin Gamora and wound up arrested by the Nova Corps. They were incarcerated in the Kyln prison complex alongside Quill and Gamora, where they also met the warrior Drax.