Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Mitchell Arthur Edgar Kosterman (born February 4, 1958) is a Canadian actor. He was in Vancouver, British Columbia, Canada. He is probably best known for his role as Sheriff Ethan Miller in Smallville. Filmography: John Doe (2003) as Sheriff Ash, Smallville (2001 2003) as Sheriff Ethan Miller, The Dead Zone (2002) as Harlan Casey, Caitlin's Way (2000), Stargate SG-1 (1999 2004) as Special Agent James Hamner/Colonel Tom Rundell- Seth (1999) as Special Agent James Hamner, - Heroes (Part 1) (2004) as Colonel Tom Rundell, - Heroes (Part 2) (2004) as Colonel Tom Rundell.