Google Play currently offers a free copy of X-Men (the first one) in HD with the installation of the Google Play channel on a Roku box. You will have to active the Google Play channle with a valid Google Play account, which is free. But once installed and linked you will be given a message stating that X-Men has been added to your account for free.
The Google Play channel was recently landed on the Roku. And to help new members build their digital library X-Men is being added as a bonus.
There is no stated expiration date for the free X-Men digital copy. Google Play is not on the Ultraviolet network, and the free X-Men digital copy can only be viewed on Google Play apps and website.