He's already battled a smoke monster. What are a few aliens to Terry O'Quinn?
The former Lost star, and current Hawaii Five-0 recurring player, has signed on for two episodes of TNT's Falling Skies. Look for him to appear this summer as a history professor who serves as a mentor to Noah Wyle's Tom Mason.
EW first reported the casting scoop.
Falling Skies averaged seven million viewers last year and was the highest-rated new drama on basic cable.