How Sex works

Falling in love and having sex for the first time are milestones which people never forget. The first episode of this three-part series accompanies young adults as they navigate this sexual territory for the first time and uncovers what is going on in our minds and bodies on the road to losing our virginity. Using CGI and computer graphics to travel inside the human body, the programme explores the physiological, neurological and psychological changes that happen before, during and after sex. It tracks one couple's ride from initial feelings to full-blown love, but it is a guessing game all the way - so is sex on the cards? The science behind their attraction is uncovered. For others with love in the bag, a wedding is the chance to confirm their beliefs and open the doors to a new level of intimacy, but will giving each other their virginity deepen their love even further? Sexual adventures are as much about finding your identity as they are about having fun, and for one gay man he has it all to do. The excitement of his first gay pride helps reaffirm his desires, but how will he cope when coming out to his family for the first time? Many people regret decisions made in the heat of the moment - we hear how abortion became one girl's only option, and for another there is exclusive access into a new surgical procedure which allows her to become a virgin again. The pressure to 'get it right' is always there, and for one group of lads a booze-fuelled holiday is the way to go. The effect of alcohol is explored, including the science behind 'beer goggles' - but will it end in sex on the beach?

This programme explores what happens to people who see their twenties as a time to play the field and explore sex with many different partners. We meet a 25-year-old man who enjoys sex so much he will sometimes sleep with four or five different women a month, and we follow a young bisexual man who regularly uses smart phone apps to hook up with other men for no-strings sex. We meet a young woman who feels she lost her virginity late, but is making up for lost time. She explains her views on the perils of monogamy and the enjoyment she takes in pursuing sex with multiple partners, and we follow her and her friends on their quests to satisfy their urges in London's vibrant nightlife. We also explore what happens when people never experience the drive to have sex, through the story of a young woman who describes herself as asexual, despite the fact she is in the first throes of a romantic relationship with a new boyfriend. We look at the darker side of sex as well. For one girl, a new life in a new city became a sexual adventure taken too far when her promiscuity started to fuel feelings of depression. We also hear how a one-time encounter was all it took for a gay man in Ireland to contract HIV. And we explore how new scientific insights into why we crave and enjoy sex help us understand the sexual choices we make at this stage in our lives.

This programme explores how sex and relationships change as we move into long-term relationships. We follow a young couple who are expecting their first child and explore the major transformation their relationship goes through on the road to this life-changing event - from the challenges of maintaining a sex life in the later stages of pregnancy to the emotional issues attached to becoming a parent for the first time. We follow a woman in her early thirties who is adamant she wants to achieve more in her career before she settles down and has kids. But with her biological clock ticking she is concerned that this decision might be taken out of her hands. We meet people whose sex life has thrown up unexpected challenges in long-term relationships, including a taxi driver who had a penile implant fitted after he struggled with erectile dysfunction once he was married with kids. We also meet a married mother of two who explains how the pressures of marriage and being a working mum have led her to explore an extra-marital relationship. And we follow a young woman whose strong drive to have a baby has been complicated by the fact she has been through the early menopause. With her husband she has decided to try and conceive through IVF using an egg donated by her cousin and we follow this emotional journey. With access to cutting-edge science and computer graphics the programme explores many of the physical and emotional issues associated with sex, love and starting a family at a crucial time in our lives when our priorities change and we start to settle down.