The fourth season of "Smallville", an American television series, began airing on September 22, 2004. The series recounts the early adventures of Kryptonian Clark Kent as he adjusts to life in the fictional town of Smallville, Kansas, during the years before he becomes Superman. The fourth season comprises 22 episodes and concluded its initial airing on May 18, 2005. Regular cast members during season four include Tom Welling, Kristin Kreuk, Michael Rosenbaum, Jensen Ackles, Allison Mack, John Glover, Annette O'Toole and John Schneider.