The Eagles used the "Hotel California" to describe the cycle of selfish, self-indulgent behavior that at first soothes and excites us, but then traps us in a cycle of dependency and emptiness. The "Hotel" is addiction, dishonesty and childishness that keeps us trapped inside ourselves until it becomes hell on earth. We can check in, but we never leave.
In this movie, Babak and his wife Neda are relatively new immigrants from Iran who are visiting other Iranian friends at a party. They had spent some time apart, but recently got back together and we blessed with a baby girl. To celebrate their reunion, they got matching tattoos.
The writer here understands "show, don't tell," and, by the time the pair leave the party, it's easy to see that the reunion wasn't entirely happy. Babak is drunk, even though he is Muslim, and Neda, who is the only one of her Iranian friends who still covers her head, isn't particularly happy about it. They bicker a bit, and, because he is distracted, Bábak runs over a cat. They decide to stay the night at the Hotel Normandie, which isn't quite the Hotel California, but it will do until something even more horrible comes along.
The rest of the movie is equal parts psychological terror, haunted house and morality play. Bábak and Neda have ugly secrets that are eating them alive, causing them to be callous and angry at each other. Their only chance to "make it to the light" is to tell each other that which they don't want to tell. Until they do, they will both be trapped and haunted by their own guilt.
The movie has a couple of moments of "gotcha" terror, but most of it is just grinding unease where the characters literally live out their deepest secrets. To tell you anymore would give it away, but this was an excellent, near Freudian study in the idea that we are truly as sick as our secrets.
Excellent script, and fascinating character study.