I Know Who You Are, series finale, BBC Four review - gripping, but no one to root for

The first thing to say is that this wasn’t the actual end. BBC Four scheduled I Know Who You Are to run two episodes a night over five Saturdays. The innocent punter might have assumed that after 10 x 70 minutes of the Spanish import, we’d arrive at some sort of terminus.

Read theartsdesk's review of the I Know Who You Are series 2 finale

It’s not in any of the BBC’s promotional literature, but in fact there are another six episodes of the drama to run [for clarification on this, see comments thread below]. If and when BBC Four broadcasts them, all these questions will play out in the style established so far: twistily, mega-absurdly and - let's be honest - grippingly. It was at least a suspenseful moment to pause in a lay-by for a breather. The past has caught up with the present: Elías has remembered he's a murderer, Ana has been located, Alicia has finally decided to do someone outside her immediate family a good turn, Eva has seen through Elías and refused to hand over the gun which (though she doesn’t yet know it) links him to the murder of Ezequiel Cortés, and Santi Mur has opted for more direct action than emetic blogging. (Pictured below: Blanca Portillo as Alicia Castro)It is, of course, posh bunkum. The plot’s chicanes and hairpin bends would test the credulity of an infant who still believes in the tooth fairy. Take Ana’s emergence from 12 days of unconsciousness. There she lay like Sleeping Beauty, unsoiled and only a little thirsty, swiftly revived by a drip that appeared out of nowhere. Santi Mur’s blogging rather tested the concept of sub judice, as did the antics of the press. Their habit of stabbing microphones at grieving relatives makes our redtop phone hackers look like cherubim and seraphim. As for his twin in a coma, Pol no sooner found out about him than succumbed to his own fit of amnesia: his only function was to prove that the Elíases know how to keep a dark secret. (Pictured below: Álex Monner as Pol)

With the plot zigzagging hither and thither like a Jack Russell with ADHD, it was easy for any viewer to miss the odd trick. But here’s a list, not exhaustive, of quibbles and niggles. It took nine episodes for anyone to work out that a six-foot grave doesn’t dig itself in one short evening. What was Cortés doing at the villa at the same time as Ana? Even though her father was dying of cancer, 100,000 euros seems rather a lot of money to leave in the possession of a money-changer in Bangkok. There was little evidence of the antagonism between Ana and her stepmother Silvia so you had to take it on trust that this was the motive for her drastic plan to emigrate rather than complete her law degree. Marc seemed bizarrely familiar with Alicia’s jogging route. Charry’s death-rattle accusation was a straight lift from the soapiest Victorian melodrama. Are university elections really that interesting to the wider media? And how come the country villa of Hector Castro had been conveniently left to crumble all these years?But like all motorway pile-ups, it was difficult to take your eyes off it. The central concept of a man who has lost his memory and thus driven a 4x4 through a whole chain of evidence was robust enough to keep an audience on its toes and wanting to know more. Integral to this was Francesc Garrido’s compelling one-note performance as Elías, a man so divided against himself he had no coordinates for defining his own reality: was he really himself with the intense, idealistic Eva (Aida Foch, pictured below) or with the evil coeval Alicia who, played with marrow-chilling conviction by Blanca Portillo, was not the best advertisement for the Spanish judiciary. That triangle has been at the heart of everything. Forget Pol and Marc and all the other pouting walk-ons. The Elías marriage was the Macbeths in charcoal-grey labelwear. Full marks to a costume department which ran with the idea that you are what you wear. Eva Durán’s joyless overcoat deserves its own spin-off series with a co-starring role for Marta Hess’s repugnant leather blouson and peroxide Monica’s push-up croptops.

As the story unfurled, a picture emerged of a toxic pair of families and a couple of sexaholic law firms in which anyone and everyone could be suspected of anything from quasi-incest to pragmatic murder (meanwhile on campus an indecisive girl drove the plot by sleeping with both a brother and a sister). It was as if Murder on the Orient Sexpress had been rerouted to Barcelona. The only real adult was Julieta (Noa Fontanals), a child old before her time who was alone capable of provoking a smile in Elías, which arrived at the 11th hour like a blue moon in a month of Sundays.What can we expect next? Pol knows that Ana has been found. Alicia, whose blood is currently smeared all over those lovely big windows, still has a pulse. Eva has made an enemy. Spare a thought for poor old Heredia, who has been imprisoned on remand, and can’t pull off the trick of bribing inmates not to kill him because Elías has already bought them a load of TVs (Spanish prisons are a bit laxer about these things than Parkhurst).

The acting has been nothing if not fiercely committed, not least from Susana Abaitua as Ana discovering herself in the company of a cold-blooded killer. It sounded good – soundtrack by Arnau Bataller – and looked sort of not very Spanish. The sun didn't shine much, and the cinematography contrived to make Barcelona hard and unwelcoming.

But then I Know Who You Are has chilliness at its heart. Everyone said "lo siento"; no one meant it. When even the missing victim, a right little trouble magnet, had attempted to entrap her uncle as a rapist, there wasn’t anyone at all to root for.

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