I spent the first two episodes of The Escape Artist wondering a) why characters in crime dramas always live in houses with floor to ceiling windows and b) why these characters never bother to furnish these windows with curtains. There were countless instances where shadowy figures lurked threateningly outside houses that could have been avoided with a quick trip to John Lewis. The final episode of the trilogy presented fewer jumpy moments, but tension levels were still high.

Not least because early on, Liam Foyle the man who murdered defence lawyer Will Burton’s (David Tennant) wife walks free, assisted by Burton’s professional rival, hard-line lawyer Maggie Gardner (Sophie Okonedo). What follows is clever, because we automatically construct our own version of the story before anything happens on screen. What would we do in Will’s position? Get away, probably, to somewhere remote. Cut to an exposed beach. Under a steely grey sky, Will and his son fish for limpets in a rocky stream. They cook the limpets in battered saucepans, outside a grey and white stone cottage. It’s peaceful. Will appears to have done as expected.

An interview with a law firm up in Scotland is followed by a drive into the remote countryside, bringing Will to an isolated pub where he asks to use the toilet. So far so ordinary. But then suddenly there he is: Liam Foyle (a chilling Toby Kebbell) slowly exiting a cubicle and washing his hands in the basin. It’s a heart-in-mouth moment. As he surveys Foyle through the bathroom mirror, Burton’s fear is palpable – Tennant’s ability to project every kind of emotion entirely authentically is never in doubt, and this scene is a prime example.

For a while we think it’s some horrible coincidence, or that Foyle is still bent on terrorising Will. Only when Will begins to follow Foyle’s car through the forest to a dilapidated cabin does it become clear that this meeting may have been planned.

But the true sequence of events isn’t revealed until the final scene, in an Agatha Christie-esque breakdown of events by a meticulous Maggie. Will’s formerly gallant-seeming bid to save Foyle’s life after an allergic reaction takes on a whole new significance in light of Maggie’s revelations. It was a satisfying ending, which was welcome given that these kinds of dramas so often end ambiguously. Nonetheless, I found myself wondering what Maggie would have done had Foyle’s body not been cremated. Her delight in having rumbled Will was evident. Would she have kept his secret quiet? And what about Will himself? He won the ‘not proven’ verdict, but could he ever truly escape from his ordeal? Probably not.

I was unsure of what to make of The Escape Artist at first. It seemed to begin as a subtle psychological piece, quickly developing into a pacey thriller. This final instalment proved it to be a cleverly constructed piece of drama, choc full of twists and turns up until the very end. Enjoyable, if not that believable - and distinctly lacking in curtains.