Sons of Denmark is the debut feature of Danish director Ulaa Salim, drawing on his observations of that country as the child of Iraqi-born parents. It is a strange film and, having found it initially engaging and even quite exciting, it left a strange taste in my mouth.

This is a conspiracy thriller with a plot that takes you to unexpected places. But it doesn’t live up to the (high) expectations engendered by its opening act – and then the film simply left me behind with a crassly violent and questionably conceived acid-attack scene, targeted at a woman, there to facilitate a revenge flourish that does not close down the narrative in any satisfactory way.

The setting is Denmark a few years into the future where anti-Muslim, anti-Arab nationalism is on the march. A white power group calling itself Sons of Denmark is creating disorder on the streets and a far-right political leader called Martin Nordahl (Rasmus Bjerg) is profiting from the mayhem, though he is careful to keep a legal distance from the violent goons who idolise him. Meanwhile, Zakaria (Mohammed Ismail Mohammed), a young Muslim man who has been radicalised by the situation, joins a secret cell and is trained by Ali (Zaki Youssef) in a plan to assassinate Nordahl. But things go awry.

In its opening stages, the film reminded me of something that Susanne Bier might have directed, or maybe a TV drama like The Wire or the Israeli thriller Fauda. There are interesting switchbacks and chicanes in the narrative, with surprises as to what and who it is actually about. But then, as it chugs on to the two-hour mark, there is that strange violent moment directed at a woman. And women haven’t exactly been important to the story before that, or after that. A disappointment.

• Sons of Denmark is released in the UK on 13 December.