Shinzon first encountered the man who would become his viceroy when Shinzon was exiled to the dilithium mines on Remus as a child. Taking pity on Shinzon, he protected him from the brutality of the Romulan guards, and raised him to consider the Remans to be his brothers.
Years later, the viceroy served as Shinzon's trusted lieutenant aboard the Reman Warbird Scimitar. In that capacity, the viceroy utilized his telepathic abilities to stabilize Shinzon, who was slowly dying from a breakdown of his cellular structure, and also to assist Shinzon in telepathically raping Deanna Troi, the half-Betazoid counselor of the USS Enterprise-E. Troi later used the viceroy's violation of her mind to the Enterprise crew's advantage, using their residual mental link to locate him aboard the Scimitar, which was cloaked, allowing Lieutenant Commander Worf to obtain a weapons lock.
Later, in an attempt to perform a complete transfusion with which to save his own life, Shinzon ordered his viceroy to lead a boarding party to the Enterprise and forcibly bring Captain Picard, the only donor with compatible DNA, to the Scimitar. The viceroy's boarding party was met by an Enterprise security team, led by Worf and Counselor Troi's new husband, Commander William T. Riker. As Worf and the security team held off the Remans, Riker pursued the viceroy into the Jefferies tubes, where they engaged in hand-to-hand combat on deck 29. Fighting on a catwalk suspended over a treacherously deep canyon in the bowels of the ship, both of them nearly fell when the Enterprise collided with the Scimitar. The viceroy was able to temporarily save himself by grasping onto Riker's legs as Riker clung to the catwalk, but ultimately fell to his death when Riker kicked the viceroy off his legs. (Star Trek Nemesis)