What happens when those whose job it is to provide security are the victims? Can they protect themselves?

The five-part Netflix series opens with the macabre killing of two police officers. To begin with, we don't see the dance of goriness. The fact that the killer murders with utmost bestiality is mentioned more than it is shown.

The killings appear random but have a set pattern: the murderer strikes through decoy distress calls, only on a Friday and at 1.15 am, and his chosen targets are police personnel on patrol duty.

Can detective Thomas Berg (Jakob Oftebro), in charge of the case, solve the confounding puzzle for himself and the viewers, who are willing captives on this ride of fear and anticipation? Help is at hand not only from his hand-picked team, including Natalie Eklund (Electra Hallman), but also his beleaguered father Alfred Beg (Peter Andersson), an ex-cop with an inglorious police record.

The love-hate relationship between the father-son duo is the backbone of the story that is at once a thriller and a psychological analysis, if not a treatise. It helps that Thomas' wife Charlotte (Lisette T Pagler) happens to be a psychotherapist.

If you thought only the Indian police is under tremendous pressure and ready to crack at the slightest trigger, think again. A similar predicament ails the police force the world over. Even smaller nations like Sweden face troubling policing issues, forcing officers to often resort to unprincipled ways.

A gay officer, John-Jo Persson (Alexander Abdalla), is even ready to give up his police badge, for he can't handle the pressure.

What is obvious is that the murderer has an axe to grind and holds a personal grudge against policemen. But there are a few red herrings. Darts don't unnecessarily fly in all directions, though a few characters, like Thomas' friend and colleague Max Abrahamsson (Henrik Norlén), do come under the radar.

As the series, high on suspense, unfolds, the circle of suspicion narrows, but the mystery deepens. The ritualistic killings have a link with an art work depicting sacrifice. In the final denouement, the line between heroes and villains blurs, if it is not completely erased. Many fall out in the line of duty. Even those who mean well make mistakes and some lose it all.

Beautifully shot by cinematographer Jorgen Johansson with a haunting score (Johan Soderqvist) to match the dread-filled atmospherics, the binge-worthy drama runs the course with a decent pace. There are very few moments when the attention dwindles.

The acting, especially by the lead actors, is organic. Peter Andersson plays the nonchalant father and a sharp mind with sleuthing skills, whose ambivalent 'now I care now I don't' attitude is particularly striking.

There is no deliberate attempt to buttress the demeanour of Peter Johansson (Magnus Krepper), the villain, even though what he does to others is shockingly depraved. More than riding on shock value, there is no sexual violence or unwarranted spicing with sex scenes; the narrative digs deep into the lives of police personnel.

Moral dilemmas are not always easy to unwrangle, ethical choices difficult to make, and even those on the right side of the law run the danger of crossing the line.

Though the series taps into the fissures within Swedish systems, it speaks in the language of universal emotions. The intriguing story of severed heads has body, heart and soul too. The taut and thrilling drama can certainly be your go-to fare in a week with lean offerings.