I Know Who You Are, BBC Four review - preposterous but hypnotic

All’s fair in love and law in I Know Who You Are. BBC Four’s latest Euro-import hails from Spain and, as per the channel’s practice, is coming at you in intense double doses, two 70-minute episodes every Saturday night.

Already it’s hard to imagine how the drama can possibly be spun out to the end without viewers getting RSI from repeatedly bitten fingernails, mopped brows and also scratched heads. It might be helpful to construct your very own wall map to keep track of the cat’s cradle of conflicting loyalties and rivalries that seem to be standard in both family life and legal practice in Barcelona (although the city isn’t named).

I Know Who You Are - Sé quién eres in Spanish, created by Pau Freixas - is a tale of two families and two legal firms, both of them subjected to intense destructive forces when a man loses his memory on the night his niece disappears, leaving traces of her blood in the boot of his crashed car. Juan Elías (Francesc Garrido), whose first name everyone seems to have forgotten because they all call him Elías, apparently has no idea if he’s guilty or innocent. When he goes back to his gleaming home (this is a drama with a lot of posh interiors) he has to learn again about the life he had before.

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

He returns a stranger to his tungsten-tough wife Alicia Castro (Blanca Portillo, familiar from Almodóvar’s Volver and Broken Embraces), who’s a top judge, and their two children Pol and Julieta (Álex Monner and Noa Fontanals, both pictured below). The latter is very much her mother’s daughter, an old head on young shoulders who can articulately deliver a long Almodovarian monologue like a veteran. The family dog (dead and dug up in the garlic section of an allotment in episode two) was flag-wavingly called Freud.What we know so far is that Elías, said to be the finest lawyer in town, was running to be vice chancellor of the university against his own brother-in-law Ramón Saura (Nancho Novo). These two alpha dogs don’t seem ever to have been close, and their rivalry wasn’t helped when Saura’s student daughter Ana decided to run her uncle’s campaign to oust her father. "Do you think he’d harm his niece?" Ramón was asked. "Without a shadow of a doubt," he replied firmly. It’s a wonder the two sisters Alicia and Silvia Castro (Mar Sodupe) were talking to each other before the disappearance. It’s a marvel they still are afterwards. Silvia like her husband has a child from a previous relationship: the volatile Marc (Martiño Rivas) seems to be the volatile outlet for both families’ latent hysteria.

Meanwhile, in the internecine vortex that is the legal profession, Elías was ferried to court through a scrum of press and police by a man who introduced himself as Heredia (Antonio Dechent), “your partner, your lawyer and your friend, but not necessarily in that order”. As Denis Lawson once said in Local Hero, people tend to double up around here. When Elías got to court his memory briefly sparked into life as he vaguely recognised one of the prosecuting solicitors and remembered that he had an affair with her when she was a student. And who wouldn't remember Eva Duran (Aida Folch), whose firm gamine features are framed by a dark nouvelle vague crop? Unwilling to exhume the past, even though Elías's partial memory reboot would destroy his defence, Eva duly removed herself from the case, but by the end of episode two she’d stormed back in after being summoned to a craftily scripted court confrontation with her former lover.This development going forward will be greatly to the relief of her pretty-boy boss David Vila (Carles Francino, pictured above with Aida Folch), whose main skillset seems to involve seduction. Among those on his horizontal case roster are the irritatingly sultry prosecutor Marta Hess (Eva Santolaria) while he's also planning to bed his bottle-blonde employee Mónica (Diana Gómez). In this world, lawyers live over the shop and are forever being dragged shirtlessly away from a shag to get on with the job. The investigation is being handled by Giralt (Pepón Nieto), a dogged old-school gumshoe from another age who is the token ugly mug in a castlist of hotties.

Phew. One understands that other jurisdictions do things differently but still: I Know Who You Are, in which everyone knows who everyone is, stretches to breaking point the concept of conflict of interest. Don’t be surprised if before the end a lawyer is found subjecting him or herself to furious cross-examination. And yet it is undeniably fast-paced, light on its feet, and densely packed with shocks. Garrido, who looks like Joseph Fiennes in 10 years, is highly watchable as the enigmatic Elías, who spent episode two discovering that he didn’t much like the person it seems he used to be. Or did he?

And then there is the character of Ana (Susana Abaitua), who briefly appeared in a flashback and revealed herself to be a flirtatious ray of sunshine. Will the story of her disappearance, and the dust it kicks up, be as compelling as that of Nanna Birk Larsen in The Killing or Léa Morel's in The Disappearance (a French drama which began life in Spanish)? After its explosive opening, I Know Who You Are feels like an endless tennis rally played out on one of those clay courts they love so much in Spain. Sort of preposterous, but hypnotic.

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