In Louis Theroux’s Altered States, the documentary-maker will look at how changing social attitudes and radical new laws have transformed the way that Americans love, die and raise children.

“I have always been interested in how people conduct the most intimate aspects of their lives,” said Theroux. “For this series we looked at the new ways Americans are approaching some of humanity’s oldest dilemmas: pregnant mums who feel unequipped to keep their babies and so pick new parents for them; the world of polyamory aka 'ethical non-monogamy'; and people with debilitating conditions who opt to hasten their own deaths.”

Louis Theroux’s Wild Weekends, the filmmaker’s first series, hit screens twenty years ago. Since then, his documentaries have covered subjects including the Westboro Baptist Church, crystal meth addicts and the Church of Scientology.

“Louis is a unique talent on BBC Two and it is always a very special moment when a new series lands,” commented Channel Controller Patrick Holland. “Altered States is a hugely challenging, disturbing and illuminating trilogy, taking us into some extremes of experience, all guided by Louis’ exceptional empathy and humanity."

The series, which has been made by the Documentary Unit at BBC Studios, will air later this year.