THE GREAT WALL (2016)
In ancient China, a group of European mercenaries encounters a secret army that maintains and defends the Great Wall of China against a horde of monstrous creatures. Imdb
This popped up on the All4 free streaming service in the UK. Initially I wasn't going to watch - then I saw it was directed by Yimou Zhang, who directed the excellent SHADOW; HOUSE OF FLYING TIGERS and the truely magnificent HERO. Matt Damon and Willaim Defoe are the "western" stars but they both look out of place. It looks great with some well filmed action sequences which is just as well as the dialogue is pretty corny, and it has an odd plot premise - when I walked a section of the wall a few years back none of the guides mentioned anything about it being built to protect against attacks from alien monsters from outer space!