The Undoing: Five reasons HBO whodunnit got people talking

With its starry leads, fabulous couture and tantalising "did he do it?" mystery, psychological crime thriller The Undoing has been one of this autumn's most addictive TV treats.

Screened on HBO in the US and Sky Atlantic in the UK, the six-part drama came to an end on Monday, but many viewers are still catching up with the series via Now TV or digital downloads.

Based on Jean Hanff Korelitz's 2014 novel You Should Have Known, The Undoing tells of a paediatric oncologist suspected of killing the mother of one of his young patients.

His arrest and trial lead his wife, a successful psychotherapist, to have doubts about the man she married and wonder how many secrets he's keeping from her and their son.

The Undoing was directed by Susanne Bier, the Danish film-maker who achieved notable success in 2016 with her BBC adaptation of John le Carre's The Night Manager.

Here are five reasons why the show has got people talking. This article doesn't reveal any major spoilers, but some of the articles it links to do - so if you would rather discover the show for yourself stop reading now.

As conflicted Manhattanite Grace Fraser, Australian Oscar-winner Kidman gives a powerhouse performance that matches her Emmy-winning turn in Big Little Lies.

For many viewers and critics, though, it is her character's stunning collection of opulent winter coats that have caught the eye.

"The real killer of the series is Nicole Kidman's wardrobe," wrote The Independent's Olivia Petter, singling out two coats of green and red velvet for particular attention.

"You know a TV show's costumes are good when they manage to upstage a murder," wrote The Telegraph's Emily Cronin admiringly.

"The Undoing might be over [but] Nicole Kidman's collection of coats will haunt me forever," penned one viewer on Twitter.

"I'm in the coat and then the coat became a part of me," Kidman told People last month. "It's my barrier and my shield from the world, but it also envelops me."

For many, Hugh Grant will be remembered most as the lovably foppish romantic lead who charmed the world in Notting Hill, Love, Actually and Four Weddings and a Funeral.

In recent years though he has appeared in more ambivalent roles, among them Jeremy Thorpe in A Very English Scandal and the devious Phoenix Buchanan in Paddington 2.

The Undoing asks us to contemplate whether his character Jonathan Fraser could be capable of brutally murdering Elena Alves, an artist and mother of two young children.

The answer to that question will not be divulged here. It is fair to say, however, that critics have enjoyed seeing the British actor stretch his wings and test our sympathies.

"Grant, playing more or less against type, is perfect casting as a man most can't help but love, even when given proof they really shouldn't," wrote Variety's Caroline Framke.

"Simultaneously charming and dangerous, Fraser is the ideal part for an aging English rogue," said NME reviewer Dan Seddon of Grant's "gritty, layered role".

In the role of Grace's wealthy father Franklin Reinhardt, veteran Canadian actor Sutherland delivers a performance of imperious grandeur and icy disdain.

Yet those who have praised the 85-year-old's acting have found it hard not to mention the follicular assistance he receives from his superior supercilia.

"Donald Sutherland's wiry eyebrows just don't quit," wrote Lauren Valenti of Vogue magazine, a sentiment shared by Jeff Sneider on the Collider website.

"Sutherland's eyebrows deserve an Emmy for their performance, helping the veteran actor to convey Franklin's power as well as his sense of entitlement," he wrote.

One of the actor's compatriots, though, did admit she "spent every episode of #TheUndoing wishing someone would comb Donald Sutherland's eyebrows".

Another Twitter user, meanwhile, expressed dismay that they didn't "get a separate cast credit".

The Undoing's cast also includes Matilda De Angelis as the unfortunate Mrs Alves, Noah Jupe as Grace and Jonathan's son Henry and Edgar Ramirez as Joe Mendoza, the detective investigating the murder.

There are also striking contributions from Noma Dumezweni and The Killing's Sofie Grabol as lawyers on either side of Jonathan's contentious murder trial.

More than one critic, however, has made the salient observation that the city of New York gets almost as much screen time as the show's human stars.

"If the characters aren't making fraught phone calls in front of shimmering New York skylines, they're perched on benches in the city's resplendent art galleries," wrote Metro's Harry Fletcher.

"Shots of sunlight glinting off Manhattan architecture add to the sense of being granted access to a secret, rich-people New York," remarked The New Republic's Josephine Livingstone.

One viewer, meanwhile, tweeted he could not wait "to go back to New York and pay $30 [£22] to go on a Grace Fraser Walking Tour while wearing a really fancy coat."

Don't worry - we're not going to reveal whodunnit. But we will say that not everyone was happy with how The Undoing's final episode played out.

The Guardian's Lucy Mangan felt particularly aggrieved, describing it as "a lesson in the value of low expectations" in which "everything fell apart".

Watching the finale, wrote Vulture's Jen Chaney, made her conclude the drama had been an "extended red herring disguised as a limited series".

The Times' Carol Midgley, meanwhile, suggested the drama ended "not with a bang but... thousands of palms slapping to viewers' foreheads".

One person who would not have been surprised by the climactic disclosure was Richard Curtis, writer of Four Weddings and director of Love, Actually.

Writing in the Evening Standard last month, Curtis revealed that Grant had texted him during shooting and "casually revealed" the killer's identity.

The Undoing can still be viewed via Now TV and digital download.

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