RJ is a very mellow guy who enjoys mediating and calming peace. When the Rangers were sent by Master Mao to find their new master in Jungle Karma Pizza restaurant, Theo mistook a patron and not RJ for their teacher. RJ is the owner of the restaurant and in turn, the Ranger's boss as well. He teaches them in a unconventional way that sometimes irritates them, but always work in the end. He has many connections that he was able to obtain morphers for his students. He also builds new arsenal for the Rangers and is very talented and skilled in the art of Pai Zhuq, but he says he is not the one to fight. His father is Master Finn wanted R.J. to follow in the way of the shark passed down by his forefathers, but when R.J. went to another master, they didn't speak for six years. When his estranged father was at mercy of Dai Shi, R.J. rescued him by unleashing the spirit of the Wolf, revealing it to them all. He saves Dai Shi when he is about to destroy them.
He surrenders himself to Dai Shi, who takes him hostage as the Rangers go 'back to basics.' R.J. was forced to fight Dai Shi in a big cage match, Dai Shi tried to steal R.J.'s wolf spirit. His wolf spirit was too strong for Dai Shi but because he couldn't have it, he tainted it. When R.J. returns, he is unable to control his wolf side and becomes a werewolf. But he doesn't share this with the others and claims it is a muscle sprain. The Red and Blue ranger even fights his werewolf form without knowing it was him. He overcomes it enough to become the Wolf Ranger to save the Rangers defeat a minion of Grizzaka. His werewolf form was agitated once again by Dai Shi's spirits released by Grizzaka and he turned against the Rangers while in the Megazords. He rescued Flit from under some debris and flit considered him his friend and wanted to repay him. He did so by enabling RJ to fight his werewolf side and merge them together. As the Wolf Ranger, RJ uses his fists, knees and feet to fight the Rinshi in a form of kick-boxing. He can activate his Wolf Morpher for extra wolf power in his attacks.
Before his father Master Finn was captured by the Phantom Beast Generals, he created a machine to help and RJ used it but it was broken by one of the Phantom Beast Warriors. He used it again to rescue his father from being encased in a Crystal Eye. Once the main three Rangers had their ceremony to become masters, RJ told Casey he taught him all he could, even when Casey was conflicted after not being awarded his stripes. He was proud of his student when he indeed earned his stripes and after the final battle, RJ continued his life as the proprietor of Jungle Karma Pizza.