Updated: Oct 6, 2019
The movie starts with a group of girls getting together for a bachelorette party. We can tell right away that there is tension between the characters. One of them is the work friend of another character, so she doesn't really fit in. Then, there's a big tension between two characters. The first one is the bachelorette and the second one is the one who lives where they throw the party. We don't know right away, but the bachelorette's sister died in a car crash, and it's the other girl who was driving. So, in ree house where the girls have the party. They hear on television that it might be contagious, and that it's extremely toxic. They lock themselves in, but things go from bad to worse.
It's a very claustrophobic movie: most of the movie happens in the house. It's also centered on the tension between the friends. It's also grounded in reality. Train accidents happen all the time. When watching this movie, the train accident at Lac-Mégantique, Québec, came to mind. Then, the toxic haze reminded me of the Bhopal accident. So, it sounds like something that could happen.
I thought the movie was quite interesting, with a lot of tension throughout. Not all the characters are lovable, but it works well with all the friction between them.
The pace is good and it keeps you on the edge of your seat. In conclusion, it's a movie to watch.