It’s one thing for a doctor to support in theory a terminally ill patient’s right to die with dignity, quite another to be the person asked to end their brother’s suffering.

When Robert, a doctor, learns that his older brother Jim, a successful rock ’n’ roll pianist he hasn’t seen in more than 20 years, has returned to England from the USA, he and his wife Barbara go to see him. While there, Jim’s wife Scarlet confirms Robert’s suspicion that Jim is in the advanced stages of cancer. Robert, against Barbara’s strongly held views, is on the verge of signing an open letter that will call for a public conversation about assisted dying, and finds himself moving quickly from supporting the idea in theory to confronting the thought of ending a person’s life in reality.

While Robert and Scarlet are drawn together, the conflicting feelings Robert and Jim have about their childhood culminate in a fierce row and Robert storms out. Jim becomes desperate for his brother to bring an end to his suffering before he loses the ability to play music, and Barbara urges Robert not to do anything that will destroy her trust in him. Robert is drawn back to visit Jim again, but will he risk sacrificing everything he’s ever worked for – his career, his marriage, even his freedom – for a brother he barely knows?