

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?
Jack Thorne
BBC One

1. Episode 1
As Marnie's health deteriorates, doctors say it's in her best interests to stop care. Defiant, her parents prepare to fight their decision. But doubt soon grows — what is right?

2. Episode 2
Andrew wavers, finding himself at odds with Nicci. With their relationship under pressure, Nicci turns to a surprising place for help. Meanwhile, Katie is torn between her parents.

3. Episode 3
Nicci's campaign becomes national news, causing trouble for Katie. Andrew doubts his choice to leave. With court looming, Nicci’s team need evidence. How far will she go to win?

4. Episode 4
In court, hope for Nicci’s case, and a surprising victory, grows. Andrew is confronted about his past behavior. As the verdict nears, who will get to decide Marnie’s future?

Sharon Horgan
Nicci

Michael Sheen
Andrew

Alison Oliver
Katie
Niamh Moriarty
Marnie

Noma Dumezweni
Samantha

Chizzy Akudolu
Mercy
Des McAleer
Eddie

Gary Beadle
Frank

Jack Morris
Tom

Pippa Haywood
Judge Spottiswood

Shane Zaza
Fred

Lucian Msamati
Derek