That's an easy one. The Empire Strikes back, a superior film in every way to Star Wars and without the insipid Ewoks of Return of the Jedi. Drama, torture, triumph over staggering odds, that Imperial Walkers battle scene on snowy Hoth, Han saving Luke from freezing to death by stuffing him inside the still warm body of his ton-ton, a cliff hanger ending and of course the immortal lines; "I am your father!" Darth Vader's shock revelation to Luke Skywalker during the brilliant fight on Bespin. Bliss. Never get tired of watching it.