Documentary following four men who have collectively helped to conceive more than 175 babies by donating their sperm to women who contacted them on unregulated websites and social media groups. These men, who donate for free, will often drive hundreds of miles to meet women at their homes, hotels or even car parks. For those featured, donating sperm sits somewhere between an obsessive hobby and addiction. Filmed over a year, cameras reveal the lengths these men will go to, as well as the potential consequences of their actions.