Best Interests: release date, plot, cast, and everything we know

Best Interests
Sharon Horgan plays the mother of a child with a life-threatening condition (Image credit: BBC)

Sharon Horgan and Michael Sheen lead the cast of Best Interests a "compelling and thought-provoking" new drama created by BAFTA-winning writer Jack Thorne. 

The highly-anticipated four-part series will tell the heartbreaking fictional story of two parents fighting to keep their 13 year-old daughter alive against medical advice.  

With TV hits such as National Treasure, Help, and The Virtues already on his CV, Thorne has shown a knack for tackling the most sensitive of subjects and viewers look set to be in for another emotional rollercoaster when this hits our screens.

“Best Interests cases are both compelling and revealing," said Jack Thorne in a BBC statement. 

"Our country has a very troubled relationship with disability and these cases put a spotlight on that. But our drama is first and foremost a love story and it needs incredible actors to bring it to life. Sharon Horgan and Michael Sheen lead a company of ridiculous talents that pull you into the most interesting of places.”

“As a parent of a three-year-old I've looked at the cases in the media about 'best interests' with some fascination and a little dread," he explains. 

"When the worst happens, how do you keep your head when everything around you feels wrong? We are going to try and tell a nuanced story that talks about this issue from all sides. ”

Here's everything we know about the four-part BBC One series...

When will Best Interests be on BBC One? 

Best Interests will air on BBC One and BBC iPlayer in four parts. The first two episodes will air as a double bill on Monday, June 12 and Tuesday, June 13 at 9 pm.

The third and fourth episodes will air the following week on Monday, June 19 and Tuesday, June 20 in the same time slot. 

Best Interests Sharon Horgan Michael Sheen

Sharon Horgan stars alongside Michael Sheen. (Image credit: BBC)

What's the plot of Best Interests? 

A BBC synopsis reads...

"This is a story of a family driven apart by having to make choices no parent would ever want to make. Andrew and Nicci’s daughter, Marnie, has a life-threatening condition. 

"The doctors believe it is in her best interests to be allowed to die, but her loving family disagree. And so begins a fight that will take them through every stage of a legal process, as they struggle to contemplate this huge decision. Who decides? And in whose best interests will it be?"

Best Interests cast - who's in it? 

Sharon Horgan and Michael Sheen will lead the cast as married couple Nicci and Andrew Lloyd, who are parents of 13 year-old Marnie, who suffers from a rare form of Muscular Dystrophy. 

Horgan rose to fame as the star of BBC Three comedy Pulling and had a major hit with C4 sitcom Catastrophe, both of which she co-wrote. She has also appeared in HBO Comedy series, Divorce, and penned BBC2 sitcom Motherland. 

Meanwhile Sheen recently starred opposite David Tennant in Amazon Prime drama Good Omens and is famed for playing Tony Blair in The Queen, Nigel Clough in The Damned United and Chris Tarrant in ITV drama Quiz.  

Alison Oliver (Conversation with Friends) and Niamh Moriarty (Jack Thorne’s A Christmas Carol), will play their daughters 17 year-old Katie and her younger sister Marnie.

Additional cast include Noma Dumezweni (The Undoing) as Samantha, Chizzy Akudolu (Holby City) as Mercy, Des McAleer (Hope Street) as Eddie, Mat Fraser (His Dark Materials) as Greg, Gary Beadle (Grantchester) as Frank, Jack Morris (Strike) as Tom, Pippa Haywood (Bodyguard) as Judge Spottiswood, Shane Zaza (Happy Valley) as Fred, Lucian Msamati (Gangs of London) as Derek and Lisa McGrillis (Mum) as Brenda. 

Best Interests

Jack Thorne has penned the four-part series (Image credit: Getty)

Sharon Horgan said: "Best Interests broke me when I first read the script and then again after talking with Jack about it. Covid seems to have shone a closer light on the desperate inequalities that exist for our disabled community so this felt very timely. 

"It’s a big subject but it’s in Jack Thorne and Michael Keillor’s safe hands. I’m thrilled to be working on this story with a super talented cast, the wonderful Michael Sheen and Noma Dumezweni, and my gorgeous daughters; Alison Oliver and Niamh Moriarty." 

Michael Sheen said: “Jack Thorne is such an extraordinary writer and he has approached this incredibly important and urgent subject with humanity, honesty and humour. I feel very fortunate to be part of this production and to work with the brilliant Sharon Horgan and some of the most talented actors around.” 

Is there a trailer for Best Interests? 

Not yet, but we'll post it here as soon as it lands! 

Sean Marland
Feature writer for TV Times, What's On TV, TV & Satellite Week and

Sean has been writing about all things telly for over 10 years and in that time he's been lucky enough to interview stars like Ian McKellen, Tom Hardy and Kate Winslet. His favourite shows are The Great British Bake-Off, People Just Do Nothing and Succession and in his spare time he enjoys drinking tea, doing crosswords and watching football.