During his 1882 lecture tour in the United States, Oscar Wilde visits Leadville, Colorado. His flamboyant personality and urbane wit win over the local silver miners as he regales them with tales about Renaissance silversmith Benvenuto Cellini.
Back in London, Wilde marries Constance Lloyd and the couple welcome two sons in quick succession. While their second child is still an infant, they host a young Canadian named Robbie Ross, who seduces Wilde, and Ross's love for him endures.
On the opening night of his play Lady Windermere's Fan, Wilde is re-introduced to the dashingly handsome and foppish poet Bosie Lord Alfred Douglas, and the two fall into a passionate and tempestuous relationship. The bond is marked by hedonism: Bosie is not content to remain monogamous and frequently engages in sexual activity with rent boys while Wilde plays the role of voyeur.
Bosie's father, the Marquess of Queensberry, a violent and cruel man, objects to the affair and publicly demeans Wilde after the opening of The Importance of Being Earnest. When Wilde sues the Marquess for criminal libel, his homosexuality is publicly exposed, and he is eventually tried for gross indecency and sentenced to two years' hard labor. Constance is advised by friends to go abroad and change her name to protect the children.
Prison life is grueling; the penal treadmill permanently wrecks Wilde's health. Bosie tells Robbie he will look after Wilde in some pleasant sunny place when he is released. Constance visits him in prison, and she is sending Cyril to school in Germany, and she may need back surgery. He tells her he has always loved her, and that he did not know himself in the beginning. She tells him she does not want a divorce. The children love him and he is welcome to visit as long as he never sees Bosie again.
Loyal friend Ada Leverson meets Wilde when he is released from prison in May 1897, carrying the manuscript of De Profundis. He goes straight into exile, to continental Europe, and later places flowers on Constance's grave. Since she died in April 1898, he is no longer allowed to see his children. He eventually meets with Douglas. A printed epilogue notes that they parted after three months and describes Wilde's death in Paris in November 1900 at age 46, alongside the fates of Bosie and Ross.
Portions of the beloved Wilde story The Selfish Giant are woven throughout the film, beginning when Wilde tells the story to his children, then as Constance reads the book to them and so on until Wilde almost finishes the story in a voice-over as the film nears its end.