After a stakeout goes wrong – really wrong – leaving one of his partners dead and the other paralysed, detective Carl Morck (Nikolaj Lie Kaas) is ostracised by his fellow officers and called in for a chat with the police chief. The chief relegates Morck to Department Q – the cold case department located in the basement of the police building. The mission is clear: sort through files and stay in the basement where nobody can see you.
Detective Morck heads to Department Q and meets his new partner, Assad (Fares Fares). Assad is thankful for the new assignment and after initial scepticism, Morck embraces a cold case, the slaying of a prominent female politician. Suspicious of initial reports suggesting the Merete Lynggard committed suicide by leaping from a ferry, Morck and Assad plunge headlong into a new investigation, and soon come to the conclusion that Merete's disappearance was a result of foul play.
The duo must unravel the mystery, fighting not just criminals, but Merete's brain-damaged brother who can't or won't speak about what happened. Add in the police chief who quickly realises Morck is not following his orders, plus a whole heap of disgruntled people left in the wake of the investigation, and the pressure mounts. This leads to some fairly predictable outcomes, including a changing dynamic between Morck and Assad – they start liking each other. After some twists and turns, everything is wrapped up nice and tightly.
The Keeper of Lost Causes seeks to ride the wave of popularity that Scandinavian crime novels and TV series have experienced recently. The film is a pretty standard crime drama, and you wonder whether anybody would be getting excited if this was an American movie. But it's not. And the always-rain-slicked pavement and bleak, colourless sky of Denmark does seem to lend itself to this genre. This certainly won't be the last Scandi crime thriller ever made. And that's probably a good thing.