BBC Two has announced a three-part series which promises "extraordinary access" to a variety of American lives.

Louis Theroux’s Altered States trilogy will literally delve into birth, sex, and death, exploring the themes lucrative adoptions, polyamorous relationships and euthanasia.

 "I have always been interested in how people conduct the most intimate aspects of their lives, " the intrepid presenter declared, speaking about the new programmes.

"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; and people with debilitating conditions who opt to hasten their own deaths.

"All of these stories have something a touch Utopian about them, involving a kind of idealism and forward thinking that brings new opportunities but also new risks.

Louis Theroux: more American lives in new trilogy

"I have been given extraordinary levels of access to courageous people and families across the United States, many of them enduring unbelievable levels of stress and anguish, and it was a privilege to be allowed into their lives in this most personal way."

The first episode examines how addiction and poverty can lead to children being handed over in exchange for money from adoptive parents.

In the second episode, Theroux visits Portland, Oregon, where he reports on the complex issues surrounding couples who opt for multiple romantic partners or "ethical non-monogamy".

In the final programme, Theroux investigates the thorny subject of euthanasia.

"Louis is a unique talent on BBC Two and it is always a very special moment when a new series lands, "BBC Two channel controller Patrick Holland declared.

"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."

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