If you have an account with Telltale, all you need to do is head over to the Back to the Future sub-site and either react to a pop-up, or follow the obvious banners.
If you don’t have a Telltale account, you’ll need to sign up for one. They’re free too, so that’s not exactly a gigantic hurdle to cross.
Back to the Future Episode 1: It’s About Time will run on PC and OS X.
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