We are fellow users here on these user-to-user forums, you're not talking to iTunes Support nor Apple - I've asked the hosts to remove your purchased details from your post.
Was there a problem with the film e.g. did it not play ? If there was then try the 'report a problem' link to contact iTunes Support : http://reportaproblem.apple.com
If the 'report a problem' link doesn't work then you can try contacting iTunes Support via this page : http://www.apple.com/support/itunes/contact/ - click on Contact iTunes Store Support on the right-hand side of the page, then Purchases, Billing & Redemption
If there wasn't a problem with the film then all purchases are considered final, but you can try the above links and see if they will refund or credit you.