It was reported back in June that actor Terry O’Quinn would be joining the CBS procedural hit Hawaii Five-0 in season 2, and now we’ve got solid evidence that his “pivotal recurring role” is going to be Bad-ass (that’s right, with a capital B). As previously detailed, “O’Quinn will play a Navy Seal Lt. Commander who trained Alex O’Loughlin’s McGarrett in Coronado, and served with his father in Vietnam. Described as strong, stubborn and a man you want in your corner when things go south, the character holds some of the answers to the mysteries surrounding the respective murders of McGarrett’s mother and father.”

Watch O’Quinn in action above, and get ready for the return of Hawaii Five-0: September 19 at 10PM on CBS.

(Hey Lost fans–how sweet is that reunion between O’Quinn and Daniel Dae Kim? It’s almost as if they never parted ways off the Island.)