- 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
Junior officer aboard the Romulan bird-of-prey that crossed the Romulan Neutral Zone into Federation space in 2266. Although mid-ranked aboard that vessel, Decius had relatives in high places in the Romulan government, and he used that influence to manipulate his commander into a more aggressive strategy when confronting the U.S.S. Enterprise.