The content is available to your choice on small private screens in the Mediatheque suite itself and it's free to view. You can either book or just show up, sit down, and watch.
The Mediatheque is open Wednesday to Sunday 11am - 8pm and Tuesdays 1pm - 8pm. It's free and you can book in advance, should you wish to do so, on 020 7928 3535. For information on some of the films available click here or visit the BFI website at http://www.bfi.org.uk.