Thunder Mountain is a 1947 American Western film directed by Lew Landers and starring Tim Holt and Martha Hyer. It was the first of Holt's 29 post war Western star vehicles and the first in a series of Zane Grey adaptations he made for RKO. It was also the first film of his written by Norman Houston who would go on to write 19 more for the star.The film began production as To the Last Man but the studio had trouble clearing the title because of a proposed Liberty Films project called The Last Man, so they used the title of the 1935 Zane Grey novel.