Riva was a famed mediator from the planet Ramatis III. He was a member of the ruling family on Ramatis, all of whom shared a genetic condition that rendered them deaf and mute. To communicate, Riva used a chorus of telepathic aides who spoke for him. The trio of telepaths represented different aspects of Riva: the "Scholar/Artist", the "Warrior/Adonis", and "Balance" who held the other two together. Riva was well known for mediating several treaties between the Federation and Klingon Empire; in fact, before Riva, there was no Klingon word for "peace-maker".
In 2365, he was to negotiate an end to hostilities on Solais V. He was transported to the negotiations by the Enterprise-D. Immediately upon meeting her, he was taken with Counselor Troi and asked her to join him for dinner that evening. She accepted and dined with Riva where she learned more about him. Riva was also fascinated with Gordi La Forge's blindness and his use of the VISOR. During the first meeting his Chorus was killed by those who did not wish peace. With his normal means of communication gone, Riva felt he could not complete his mission. However, after some convincing by Deanna Troi, and with the assistance of Commander Data who learned sign language so that he could function as an interpreter, Riva continued his work. Riva decided to bring the warring sides together and teach them sign language, which would help bond the factions and provide common ground to aid in negotiations. He stayed on Solais V to begin the process of peace. (TNG: "Loud As A Whisper")