William Shatner is an actor.
William Shatner ( born March 22 , 1931 ) is a Canadian actor , author , producer , and director . In his seven decades of television , Shatner became a cultural icon for his portrayal of James T. Kirk , Captain of the USS Enterprise , in the Star Trek franchise . Shatner also appeared in the NBC series , 3rd Rock from the Sun in seasons 4 and 5 as the role of the `` Big Giant Head '' whom the alien characters of the Series reported to .