- Star Trek: The Motion Picture
- Star Trek II: The Wrath of Khan
- Star Trek III: The Search for Spock
- Star Trek IV: The Voyage Home
- Star Trek V: The Final Frontier
- Star Trek VI: The Undiscovered Country
- Star Trek Generations
A tall, patrician male Romulan who serves as a spokesman for the Elysian Council in the Delta Triangle, a region of space containing a pocket of alternate space in which dozens of space vessels have become irrevocably trapped over the centuries. Because Xerius had made numerous failed attempts to escape from Elysia after having been marooned there, he advised Captain Kirk of the U.S.S. Enterprise and Captain Kor of the I.K.S. Klothos to accept that they were fated never to see their homes again. Despite Xerius's warning, both ships, captains, and crews escaped from Elysia on stardate 5267.6 (2269).