Molly (Cecilia Milocco) is released from secure accommodation having been committed there after the trauma of a personal loss. Her new accommodation is plain though workable and she still has possession of her personal goods. Still deeply traumatised Molly sets about getting back to some sort of normality by the simple tasks of unpacking and going out shopping.

At night however she’s disturbed by a knocking coming from her ceiling at the same time that a red patch appears. Her neighbours don’t know anything about it and when she reports what she thinks is an assault it turns out to be a tiff.
The knocking continues leading Molly to become more and more stressed over as she also starts to hear a woman crying. With the police on the verge of cutting her off she takes matters into her own hands.

At 74 minutes Knocker is a lean efficient psychological thriller with a very good central performance from Milocco as Molly. With the script by Emma Broström and Johan Theorin (on whose novel this is based on) director Frida Kempff keeps the camera tightly focused on Molly the viewer is granted her perspective on the situation, her frustration with the people around as well as her trauma.

There’s a vague recollection of Polanski’s Repulsion here though that film works on a far more visceral level than this one. More effective and I would suggest by design is the dilemma that Molly faces that no one will believe her and that they are all men. She’s seen as an irritant and timewaster even when she reports a fight between her neighbours who later deny all knowledge of it. You do start to feel some sympathy for her and maybe that could have done with some fleshing out.