Looks like I'll need to start watching Hawaii Five-O.
Terry O'Quinn has signed on to be reunited with former Lost co-star Daniel Dae Kim on the CBS drama, as he'll come on board in a critical recurring role: The Navy Seal Lt. Commander who trained Steve McGarrett and served with his dad in Vietnam.
Look for O'Quinn's character to possess vital knowledge over the murders of McGarrett’s mother and father. He'll appear on multiple episodes.