Thomas is a minor villain in the fourth season of Arrow. He is a leading member of H.I.V.E..
Thomas is a member of H.I.V.E., acting as one of its leaders. He is also part of Operation Genesis. When Damien Darhk calls for a board meeting, Thomas is one of the leaders not physically present, as he lives in Madrid. He joins the meeting via screen. When Milo Armitage, another H.I.V.E. leader, claims that there is still some concern about the Star City operation, Thomas interrupts, saying that Armitage is too polite to say that the entire phase depends on Ruvé's questionable political knowledge.
Darhk then turns to Thomas' screen, claiming that he remembers taking a siesta in Thomas' office once and that he can still picture the room as if he was there in person, stressing the last part. By use of his magical powers, Darhk then kills Thomas, breaking his neck by the sounds of it. The meeting then continues as if nothing has happened.