Dublin Murders, BBC One

Set in 2006 and adapted from In The Woods and The Likeness, the first two novels in Irish-American writer Tana French’s bestselling Dublin Murder Squad series, Dublin Murders took the classic him-and-her detective pairing, gave it a twist, then placed it in the sort of eerily heightened setting familiar to readers of Gillian Flynn novels. Call it Irish Gothic, if you like.

The twist in this case is that our detectives – sharp-suited Rob Reilly (Killian Scott) and army surplus-wearing Cassie Maddox (Sarah Greene) – are both hiding secrets from their pasts. Hers was partially revealed towards the end of the second episode when a nocturnal visit from a man called Frank threw the name Lexie Mangan into the mix. An alias from Maddox’s previous undercover work? Her real name? Someone else entirely? We were left guessing, though there was no doubt as to the nature of Frank’s warning to Maddox: it was one of those warnings that sounds very like a threat because that’s exactly what it is.

Reilly’s past, however, went to the heart of the case under investigation – the murder of Katy Devlin, a talented young ballerina from rural Knocknaree, whose body was found placed on a stone slab in the middle of an archaeological dig.

In the best traditions of detective noir the killing was an echo of a similar case from 20 years earlier when three children had gone into the same woods and only one, Adam, had returned, traumatised and unable to remember what had happened. And Adam, we learned in episode one, was Reilly. Shipped off to boarding school in the UK after his ordeal he later returned to Dublin every inch the Englishman, joined the police and established a new identity as Robert, his original middle name.

Fleshing out the events from the 1980s was a series of flashbacks in which we saw Adam and his friends Jamie and Peter, and an older gang of boys headed by Jonathan Devlin (Peter McDonald), who later married the only person who could give him an alibi for the night Jamie and Peter disappeared and who is now mourning the loss of his daughter, Katy.

So yes, there was a lot going on. But with French herself joining the script-writing team alongside veteran EastEnders writer Sarah Phelps Dublin Murders never felt tangled or muddled, and Scott in particular brought an unsettling air of menace. To say he has hinterland doesn’t begin to explain the bizarre sexual relationship he has with his “landlady”, Heather. Dublin never looked more gloomy, threatening or beguiling.