Reger

From Memory Alpha, the free Star Trek reference.

Reger in 2267
Species:	Betan
Gender:	Male
Actor:	Harry Townes

Reger was a citizen of Beta III at the time the USS Enterprise visited in 2267. He was part of a resistance that was organized in threes; Tamar was his contact, and he did not know who the other member of the cell was. He provided a refuge for the landing party when they sought to escape the mayhem of the Festival, and later led them to a safe haven. After Landru discovered and abducted the landing party, Reger was able to slip away; he was somehow immune to absorption. Although part of the resistance, when he was confronted with an actual attempt to end Landru's rule, he recanted and attempted to betray the landing party to the lawgivers. (TOS: "The Return of the Archons")