Dominic is a friend of RJ's. Years ago, they were both at Pai Zhuq together. Dominic was & is so good a the Rhino Spirit, that Master Mao was going to choose Dom to be one of the guardians. However, Dominic had a curious streak with always wanting to see & do everything. So Master Mao sent him out on a quest to find a focus, and told him he would find his path when he least expected it.
When Dominic showed up in Ocean Bluff, he was only going to stay a couple of days. The first impression he made on the members of the Ranger team weren't good, due to his carefree and joking attitude. After seeing the RJ and the others were Power Rangers fighting the Rinshi, Dominic asked to become a member of the team, but Casey & Theo wouldn't allow it.
Dominic tried to prove himself by working hard at JKP, but he still ended up making mistakes in the parlor and in the loft as the team trained. He decided that since he wasn't needed, it was time to pack up and head back out on the path. However, when Fran caught up with him, she told him that he shouldn't give up on himself. When Fran walked up, a sign started to fall on her from a crane, but Dominic jumped to the rescue. He used his Rhino powers to cut the sign and save Fran.
Casey saw all this happen, and realized that he had never really given Dominic a fair chance. When the city came under attack again, Casey asked Dominic to join the team.
Dominic was then given a Pai Zhuq bracelet by RJ. This allows him to summon his Rhino Morpher and Morph into the Rhino Ranger. As a Ranger, Dominic can really show his expert skills with the Rhino Spirit. He is a fierce fighting and can also use his joking attitude in battle to throw enemies off.
When Dom remember abut the Control Dagger Master Mao had given him before his quest, Dominic & the others set out to find the dagger and to unlock the Rhino Power at the Rhino Nexus. After a fierce battle between the Rangers and the Overlords, as well as Daishi getting the dagger, Dominic was finally able to get the dagger back, and release the power of the Rhino Steel Zord.
Dominic also worked at Jungle Karma Pizza with the rest of the gang, but he still had his joking attitude that everyone had grown to love.
In the final battle against Dai Shi, it took help from Camille & Jarrod to help weaken Dai Shi. But only the chosen three could destroy Dai Shi. Together Casey, Theo & Lily reached a level of power no one had ever achieved before. This powerful attack was able to destroy Dai Shi for good.
After the battle was over and won, it was time for Dominic to head back out and see the world, but before he left, he asked Fran if she would like to join him. She said yes and the two would set off backpacking through Europe.