Once Upon a Time in the West (1968)

Henry Fonda's chilling performance as Frank marks a masterstroke in cinema history, and his casting against type delivers a twist 30% more shocking than the average spaghetti western villain reveal. Made for $5 million and structured like a Wagnerian opera with each character assigned an individual Ennio Morricone leitmotif, this 165-minute operatic masterpiece stands as Leone's most ambitious work. Although it earned $5.3 million domestically—less than half of #1 The Good, the Bad and the Ugly's total—its critical reputation has grown, with a 96% Rotten Tomatoes score surpassing that film's 95%. The film's measured pacing and emotional depth influenced later directors more than any other entry on this list.