Sub-Commander Thei was the first officer to Commander Tebok aboard a Romulan Warbird.
He was part of the investigation into the destruction of several Romulan outposts near the Romulan Neutral Zone in 2364. (TNG: "The Neutral Zone")
Sub-Commander Thei was played by Anthony James.
"TIE" was the pronunciation for this character's name from the script pronunciation guide.  However, his name was not spoken onscreen.