Travelling across the United States, acclaimed documentary filmmaker Louis Theroux sees how the internet and social media has impacted some of the most controversial corners of American society. From those promoting far-right ideas, those in a violent and chaotic rap scene and adult film performers claiming victimization by the industry. All use the internet to reach their audience, all push the boundaries of acceptability. Watch Louis Theroux: Forbidden America in the US: https://bit.ly/3CuEltr and Canada: https://bit.ly/3CpQFuK with BBC Select.