Can the rulebook on relationships be rewritten? Louis Theroux takes a look.

Love and marriage. Do they still go together like a horse and carriage – or is the model no longer fit for purpose?
Watch Louis Theroux: Altered States - Love Without Limits and more acclaimed documentaries on BBC Select today. Restrictions apply*.
Louis Theroux: Altered States - Love Without Limits on BBC Select
British filmmaker Louis Theroux visits ‘US capital of polyamory’ – Portland, Oregon – to meet the couples opening up their relationships in eye-opening ways. For many, more partners means more love and happiness – but for some, he finds, it means jealousy, upset and broken hearts.
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