Save up to $20 on Back to the Future Movies 10/21/2015 By MFA Leave a Comment This post may contain affiliate links, please see my disclosure policy. In honor of Back to the Future Day, Best Buy has up to $20 savings on the movies. The 30th anniversary trilogy on Bluray is $24.99. Amazon is selling this for $5 more so a nice savings. You can see all the options here. The sale is 10/21 only.