Hunt said she spent much of her screen time "utterly naked. My jaw dropped at the prospect. But then I thought, 'Do I care about what people think of my body or do I care about being part of a story that is beautiful?' At the end of the day I cared more about that." Set during the 1980s in Berkeley, California, the film is based on the true story of journalist and poet Mark O'Brien who was paralysed with polio, and confined for hours every day to an iron lung.
Aged 38, Mark (played by John Hawkes) decided he wanted to experience sex for the first time and hired a sex surrogate, Cheryl Cohen Greene (played by Helen).