Nijil was a male Romulan who lived during the 22nd century and was a leading scientist within the Romulan Star Empire. His contributions was critical in the early-phase of the Earth-Romulan War, until he was executed by Admiral Valdore for his involvement with the radical political group Ejhoi Ormiin.
In 2154, Nijil was assigned to Admiral Valdore's project which involved an attempt to destabilize the Alpha Quadrant and the Beta Quadrant by preventing the various powers from uniting. To accomplish this, he made use of a special project which involved Telepresence drone ships that were piloted remotely by a captured Aenar. Through the ship, Nijil helped masquerade Romulan attacks as being perpetrated by another power in order to increase tensions in the quadrants. Ultimately, the plan failed due to intervention from the Earth ship Enterprise. (ENT episodes: "Babel One", "United", "The Aenar")
By the next year, Nijil had risen to the rank of Chief Technologist within the Romulan Star Empire and once again got to work with Valdore after he was freed from imprisonment by First Consul T'Leikha. He attempted to resurrect the telepresence drone ship project by capturing more Aenar from Andoria through the use of Orion mercenaries but their plan was stopped by the Starfleet ship Enterprise. (ENT novel: The Good That Men Do) With the failure in the development of that technology, he helped spawn a spin off technology by creating the arrenhe'hwiua telecapture system as well as being involved in the secret assassination of Doctor Ehrehin i'Ramnau tr'Avrak. (ENT novel: Kobayashi Maru)
Nijil was a member of the Ejhoi Ormiin, a Romulan political group attempting to take power in the Empire. Nijil also worked with Valdore and T'Leikha to assassinate Praetor D'deridex and then with T'Leikha to assassinate Valdore. D'deridex was successfully killed, but Valdore survived. (ENT - The Romulan War novel: Beneath the Raptor's Wing)
In 2156, Valdore discovered that Nijil was a member of Ejhoi Ormiin and was attempting to join his rebel compatriots by having them "kidnap" him from the Eireth. Valdore attacked the Eireth and captured Nijil. Valdore then offered Nijil the Right of Statement and informed Nijil that Romulan mind probes would be used on him. Shortly afterward, Valdore had Nijil killed. (ENT - The Romulan War novel: To Brave the Storm)
- ENT episode: "Babel One" (first appearance)
- ENT episode: "United"
- ENT episode: "The Aenar"
- ENT novel: The Good That Men Do
- ENT novel: Kobayashi Maru
- ENT - The Romulan War novel: Beneath the Raptor's Wing
- ENT - The Romulan War novel: To Brave the Storm