When making a movie about dreams, it is incredibly easy to become disjointed in the narrative because you take narrative shortcuts when you storytell through dreams, which the audience can sometimes fail to connect with. This movie suffers from that to a lesser extent and manages to tie it back together after the twist, which happens later on in the movie. From then on, the dream sequences are more cohesive, and you get more stakes into the characters. It's not a perfect movie by any stretch, but it does engage and the characters have enough depth for you to be involved with them in order to build tension.