Movie streaming services are fine, but as their respective libraries and monthly rates change, nothing compares to having the 4K Blu-rays of your favorite movies to play whenever you want. If you want to add some titles to your collection, several great films and box sets are selling at the lowest prices of the year, and some of our favorites are under $20. Unsurprisingly, many of the films we’ve included below will be great to push your entertainment center to its limits. These big price drops are here because of Amazon’s Prime Big Deal Days, the two-day sale that lasts through Thursday, October 9th, at 3AM ET /12AM PT.