America's college fraternities are notorious for hard drinking and hard partying, but they are also accused of fostering a culture of brutality and sexual assault. During one term at the University of Central Florida, the BBC's award-winning This World programme follows the life of a group of frat boys as they embark on the pledging process, when new recruits have to prove themselves before they can become a fraternity brother. Most kids are joining because fraternities provide access to a powerful network of alumni throughout the US. But each year, students die or are injured in barbaric initiation rituals, known as hazing, and some argue that the way fraternity system is set up allows sexual assaults to occur during drunken campus parties. Research has shown that fraternity men are three times more likely to sexual assault than non-fraternity men.