'Best Interests' is the Best of Television

Who and what determines someone’s quality of life? Is there a right time to stop fighting for your child? How do you know what is in their best interests? These are the questions the fabulous new series Best Interests considers with heartbreaking authenticity. Already a success in the U.K., where it debuted in 2023, the four-episode series follows Nicci (Sharon Horgan) and Andrew (Michael Sheen), whose daughter Marnie (Niamh Moriarty) was born with congenital muscular dystrophy. Nicci and Andrew’s entire life is structured around and dedicated to the care of their daughter.

The series opens with the pair returning from a rare weekend respite. They are still so crazy about each other that they briefly try to get busy in the bathroom on the train ride home. But once home, they soon realize Marnie has spiked a fever. This is not an infrequent occurrence. However, sadly, that’s the last time we see Marnie in the present-day alert. She has a severe chest infection. Plagued with guilt, Nicci worries that they would have noticed something was wrong earlier if they had been home. “You didn’t do anything wrong. You’re excellent parents,” Marnie’s doctor, Samantha (Noma Dumezweni), kindly tells them.

Nicci and Andrew think this hospital stay will be like the others, and they will soon be able to bring Marnie, now 13, back home. But this time, it is different. Marnie’s body is deteriorating. Every time she is intubated, it damages her fragile body even more. Samantha thinks it’s time to start discussing palliative care. A furious Nicci is not ready for that discussion. “She still laughs. She still loves. I can still see so much inside her,” she says. Suddenly, the doctor who has cared for Marnie all of her life has become her adversary. Things go from bad to worse when Marnie suffers a cardiac arrest and may have brain damage.