I have just finished watching The Killing II. There won’t be any spoilers here; I’m not going to talk about individual plot twists and developments.

I’d heard this series was not as good as the first one, and I agree that it’s not quite as compelling. But that’s partly because it’s trying to do something different from the first series.

One of the things that made the first season so intense and gut-wrenching was the show’s strong focus on the effect of the crime on the victim’s family. The investigation followed both the police and the family in equal measure, taking us into highly emotional territory. The new series doesn’t do that – we see very little of the families of the victims – and it investigates a series of linked crimes rather than just one killing. It’s not about the emotional fall-out of a crime – although you could argue that it’s about a different kind of fall-out: the political fall-out known as blowback.

What it does share with the first series is a dazzling ability to keep twisting and turning; to keep setting up new prime suspects, episode after episode, and make each one believable and intriguing, so with each new episode you finally feel like you’re uncovering the real truth. But then the plot keeps turning, the discoveries keep coming, and what seemed so clear is unravelled, to be replaced by another, equally plausible explanation.

This is the show’s genius, and it’s what makes it so maddeningly compelling. There is never just one suspect, or one or two, who are eliminated one by one. The show’s action throws up one completely believable scenario after another, leading you ever deeper into the darkness.

If the latter half of the second season has been marked by a tendency for the investigating characters (Sarah Lund, and the Justice Minister, Thomas Buch) to lecture people about their responsibilities to their office, or the truth, which then prompts them, not entirely believably, to do the right thing and confess something, there are enough turns of the screw and surprises to make this series ultimately very compelling, in that “let’s watch just one more” kind of way.

Which leads me to a question for any crime fans out there. The Killing uses highly complex plotting designed to uncover one question: who is the perpetrator? In both series, this question is never conclusively resolved until the last episode, and the exploration of opportunity/character/motive, the spinning out of possible scenarios, is what makes it so exciting. But what if the perpetrator’s identity wasn’t a mystery until the end? Could you still make it suspenseful? I’m particularly thinking of TV here – novels can get away with that sort of thing.

But can you make a TV show about a crime compelling and exciting if the audience already knows whodunnit?