Dr. Henry Shaw is a paleontologist and recurring character. Later on, he is revealed as the villain Belloc and acted as the leader of the Order of Anarchy who sought to become the master of darkness. These actions made him the primary antagonist of the show.
It is later revealed that he was manipulated and influenced by Yao Long (using his voice and keeping his identity hidden) to rebuild the dark Nexus stone while the latter was inside Shaw's yo-yo. After Henry rebuilds it, he thought that he'd reached his goal, but discovers that it was all a ploy to release Yao Long. He was then stripped of his yo-yo and forced to leave the Nexus.
In The First Yo, Henry was under a bridge, digging his way into the stone beneath it, while guided by the voice of Yao Long. He dug out a fully dark powered yo-yo, powered it up with his Yo Kwon Do energy and became Belloc.