I recently saw the original 'Martyrs' and absolutely loved it. That French film from 2008 was very close to a horror masterpiece. It was original, disturbing and clever. An absolutely marvelous film. So of course the Americans were going to have a go at remaking it - I'm just surprised it took them so long. Now, there are a number of reasons you might remake a film. You could think there were areas that could have been improved on in an otherwise good film, or you might simply want more people to see such a wonderful story. Whatever your reason is for doing it though, one thing is absolutely crucial - you must maintain the quality. Otherwise you are doing a massive disservice to the original and tarnishing its name. Sadly, that's exactly what the 2015 version of 'Martyrs' has done.
The first 3/4 of the film remain extremely similar to the original, almost feeling like a shot-for-shot remake at times. During this phase the movie isn't actually half bad. The same intensity isn't quite there and the acting is step down, but it could be considered a passable film up to that point. Then the final 1/4 begins and it all starts to unravel. This was always going to be the segment that determined how good this film was going to be, because it was the segment that made the original what it was. Everything that made the original ending great was basically removed and replaced with inferior ideas. I would've preferred to see zero creativity used and simply a shot-for-shot, word-for-word remake created, simply because people who see this instead of the original are going to get a bad taste in their mouth, when they should have exactly the opposite.
This remake of 'Martyrs' never dares to be great, and that it why it isn't. Whether they were afraid American audiences wouldn't be able to handle the gruesome violence and ambiguity of the original I'm not sure, but if that was the case it makes zero sense because the only people who are going to see a film like this are the ones that can handle it. It's a terrible shame this movie was ever made. If it's not too late and you haven't seen either version yet, I implore you to choose the French original. It'll be the wisest decision you ever make.