Goodnight Mommy first debuted at Fantastic Fest in 2014, and has since become one of the most anticipated horror films of this year. As you can see in the first trailer, Austrian directing duo Severin Fiala and Veronika Franz have crafted a wholly unnerving psychological horror story about two boys coping with some…changes…in their mother.

Goodnight Mommy will definitely be remembered as one of the best horror films of 2015. It’s an exceptional, brutal piece of work, and one that will really give your nerves a work out. The film centers on two brothers whose mother returns home from undergoing some mysterious facial surgery — but her face isn’t the only thing that’s different about her. What follows is an unsettling and sometimes uncomfortable psychological back-and-forth between mother and sons. To say much else would spoil it.

In the heat of the summer lays a lonesome house in the countryside where nine year old twin brothers await their mother’s return. When she comes home, bandaged after cosmetic surgery, nothing is like before and the children start to doubt whether this woman is actually who she says she is. What ensues is a terrifying observational struggle with fatal consequences.

Goodnight Mommy stars Susanne Wuest, Elias Schwarz and Lucas Schwarz, and hits theaters this September.