Sex is a simple word for a very complex set of desires. It cuts to the core of our passions, our wants, our emotions. But when it goes wrong, it can be the most painful thing of all. Professor Alice Roberts looks through 45 years of Horizon archive to see how science came to understand sex, strived to solve our problems with it, and even help us to do it better. Can science save the day when sex goes wrong?

Filmed over 5 years, A Syrian Love Story charts an incredible odyssey to political freedom. For Raghda and Amer, it is a journey of hope, dreams and despair: for the revolution, their homeland and each other.

Documentary that looks back to the furore caused by Princess Margaret's affair with Peter Townsend, a divorced commoner. Billed as a constitutional crisis, Margaret's dilemma was the first modern royal scandal which would shape the future of royal relations with the media. In 1955 she chose to sacrifice love for duty by ending the affair, but new evidence presented here suggests that hers was a needless sacrifice.

A reality thriller that is a shocking product of our times, Catfish is a riveting story of love, deception and grace within a labyrinth of online intrigue.

Born and raised in Iran, film-maker Nahid Persson returns there to meet a 50-year-old man with four wives, twenty children - and an irascible, foul-mouthed mother

This story of the lives of three Australian women told with remarkable honesty demonstrates how fascinating and complex so-called 'ordinary' life can be.

As more young couples reject arranged marriages in modern India, Unreported World investigates a wave of violence that's left hundreds dead across the country's northwest states.

Reporter Marcel Theroux and director Frankie Fathers join some of China's many millions of male lonely hearts on their search for a wife, and meet some of the 'Love Hunters' working to find them an ideal bride.