Sulan was the chief surgeon of the Vidiian Sodality, who operated from the hidden Vidiian base on Avery III. In 2371, the USS Voyager was surveying the Avery system when Lieutenants B'Elanna Torres, Tom Paris and Pete Durst were captured by the Vidiians.
Sulan believed that Torres' Klingon DNA was resistant to the phage. To obtain a pure test subject, he split her into two individuals -- one completely human, the other Klingon -- using a genotron, and then infected the Klingon Torres with the phage. Sulan was gratified that Torres' Klingon physiology appeared to be successfully resisting the phage. He came to greatly admire the Klingons, telling Torres that they were the "most impressive species" he'd ever seen.
After Durst was killed for his organs, Sulan grafted his face over his own in hopes of winning her favor. However, Torres was appalled and escaped, strangling Sulan. His research was never completed. (VOY:"Faces")
- Sulan was played by Brian Markinson, who also played Durst.