Based on the real-life scandal that shocked Victorian-era England, this movie tells the story of Euphemia "Effie" Gray (Dakota Fanning). At nineteen, she married the prominent art historian and critic John Ruskin (Greg Wise), but Ruskin refused to consummate their marriage. Lonely and frustrated, Effie is drawn to pre-Raphaelite painter John Everett Millais (Tom Sturridge), and finds a friend and champion in Lady Elizabeth Eastlake (Dame Emma Thompson). After five years trapped in a loveless marriage, Effie will defy the rules of Victorian society.

Set in the Pacific Northwest, USA, The Cannon is an emotionally charged comedic drama that centers around an aging adult film star, Colton Clemens, who struggles to hide a terminal illness, and true profession, from his impressionable, adolescent daughter before she moves out of the country with his ex-wife. Determined to leave behind a legacy that his aspiring-actress daughter can be proud of, he makes a desperate -- and virtually impossible -- attempt to convince famed director Gina Passmore to allow him to star in the lead role of a feature film adaptation based around the iconic play his late mother once made her own legendary debut in. Colton's crusade to right past mistakes collides against the new direction that management at the porn studio imposes on him for their adult content, and he is forced to cross his most personal ethical boundaries to comply, though doing so sets off a chain of events that causes everything in his life to suddenly implode. As Colton confronts the repercussion of his choices, he must ultimately decide whether to give up his identity as "The Cannon" and try to salvage the relationship with his daughter, or accept that he's never going to become more than what he's known for in his profession and try to hold onto the only bit of recognition he's ever achieved as a performer.