NW, BBC Two

“Why is everyone from your school a criminal crackhead?” “Why is everyone from yours a Tory minister?” These questions lie at the heart of Zadie Smith’s NW. Keisha (the wonderful Nikki Amuka-Bird), aka Natalie, is married to wealthy Frank (Jake Fairbrother), who’s asking the crackhead question. Leah (Phoebe Fox), who answers back, is her best friend – though that’s no longer a given.

Keisha and Leah went to school together and grew up on Caldwell, a Willesden estate; they still live nearby. Keisha is a success story, a perfectionist black barrister – “Life was a problem that could be solved by means of professionalisation” – whose Caribbean mother told her she had to be twice – just twice? – as good as everyone else in order to get anywhere. Part of that involved re-naming herself Natalie, with mixed results. Leah is Irish/English, more low-key, works for a charity. She’s married to Michel (Cyril Guel), an Algerian-Guadeloupian hairdresser.

Natalie – two kids, big house near the park and a half-Italian, half-Trinidadian husband – has a brittle demeanour and gives posh dinner parties. Leah and Michel - council flat, one dog – are invited, but Leah thinks it’s just to give local colour and make Nat, who’s dressed like “some fucking African queen”, seem interesting. The childhood friendship is cracking at the seams. “Be careful or you’ll become this English person who hates their friends,” warns Michel in his sexy French accent.

Rachel Bennette’s excellent adaptation, beautifully directed by Saul Dibb (Amuka-Bird also starred in his adaptation of The Line of Beauty), captures much of the essence of Zadie Smith’s fragmentary, stream-of-consciousness novel, with her superb dialogue intact. But it’s too short (you’ll want to re-read the book). Some of the most vivid bits in the novel are the descriptions of Keisha and Leah’s childhoods. Their backstories, inevitably lost to some extent in a 90-minute version, are important – it’s in childhood that differences begin. Nathan (Richie Campbell), who used to be good at everything, including maths, and got a trial with QPR, is now a homeless loser. Back in the day at Brayton, the local comp, he was a hero, fancied madly by Leah. Everyone loves a cute little 10-year-old-boy, he tells Natalie when they run into each other on Carnival weekend, but for a black man, “There’s no way to live in this country once you’ve grown. No one wants you.”

There are lots of bitterly sad moments in NW, and even the happiest ones don’t last long. Felix (O-T Fagbenle, pictured above), a real charmer, is on the up, now he’s off the drugs and has a positive-thinking girlfriend who tells him how to harness the power of the universe. His dad Lloyd (Victor Romero Evans – a great cameo in one of the funniest scenes) still lives on Caldwell, listening to reggae in a fug of weed. Felix visits but doesn’t stay long – he’s got places to go, people to see. “Only you’ve got the power to destroy your life,” he tells the MG-owner he’s in the process of ripping off. Not quite true.

Natalie, whose story is the most powerful, is in the process of destroying her marriage, though she doesn’t know why, only that she wants to break something open. She registers with a hook-up site and has sex with strangers, reverting from her high-flying Natalie persona to Keisha, a hairdresser (hilarious scene with overwhelmed Dinesh from Wembley: “You’re quite strong-minded, innit, Keisha. I’m feeling a bit hot and bothered if I’m honest”). She seems hollowed out and lost. A crisis forces her to rediscover her bond with Leah in an uncharacteristically sentimental scene. They’re united in informing on Nathan to the police. The right thing to do? There are no easy answers in NW.

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