Just watched Ils/Them. It's not quite rewarding, per se, but it is a pretty solid thriller with nicely executed suspense and some likable "protagonists." It's supposedly based on true events and that makes it a much more significant experience. It's not really a slasher and doesn't rely on gore, but is still quite visceral and should evoke a fair amount of empathy for the starring couple.
It's a Romanian film, shot in French with French actors, but there's little actual dialog so subtitle haters can easily enjoy this one quite easily.