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In "The Unholy Three" (1925), Lon Chaney portrays Professor Echo, a ventriloquist who masterminds a series of robberies with his two accomplices, a strongman and a female thief. Chaney's performance as Echo is particularly memorable for his skillful use of ventriloquism, creating a distinct and sinister character. The film showcases Chaney's versatility as an actor, as he effortlessly switches between the roles of Echo and his dummy, "The Dummy."