Gregory Phillip "Greg" Grunberg (born July 11, 1966) is an American television and film actor. He is best known for starring as Matt Parkman on the NBC television series Heroes (2006-2010). Other notable roles include the characters Sean Blumberg on Felicity (1998–2002), the pilot Seth Norris on Lost, Eric Weiss on Alias (2001–2006), X-Wing Pilot "Snap" Wexley in Star Wars: The Force Awakens (2015), and as exterminator Alex Mathis in Big Ass Spider! He has often appeared in works produced and directed by childhood friend J. J. Abrams. He is a recurring cast member in the first 2 seasons of the Showtime American television drama series Masters of Sex.