Trivia

Famous among Star Trek sequel fans for his portrayal of Chancellor Gowron, supreme leader of the Klingon Empire.

"Duras!" and "Gowron!" (O'Reilly's character Klingon Chancellor Gowron and his enemy Duras; from The Next Generation and Deep Space Nine) are quoted when clicking on the Protoss Carrier unit in the computer game "StarCraft".

Has made guest appearances on two different series in which one of the main characters was a shapeshifter: Manimal (1983) and Star Trek: Deep Space Nine (1993).