This week on Four Corners, British filmmaker Ben Zand takes us into the dark world of Incels – a radical online subculture of young men who rage against women for supposedly denying them sex and then turn that rage into fantasies about horrific violence.Zand uncovers the shockingly violent content that is being shared online and talks to the men behind it, in an effort to understand the Incel mentality that has in part lead to hate crimes and in some cases mass murders.The film also explores the intersection between loneliness and young men's vulnerability to online radicalisation – a practice known as black pilling. This culminates when Zand accompanies one young man to a bar to meet and talk to a woman for the very first time.