The story of human biological creation. The programme follows the progress of a couple who are expecting triplets, from the 4D scan when they first come face-to-face with their babies to the dramatic finale of birth. Plus, meet a woman expecting her 16th baby and the oldest conjoined twins in the world.

In this episode, Michael Mosley shows how existence is a struggle and how, minute by minute, from your first breath to your last, your body performs countless small miracles to keep you alive.

Michael Mosley traces our development from birth to adulthood, and reveals that the human brain is so sophisticated it takes more than twenty years to mature.

Michael Mosley reveals the ingenious ways in which your body defends itself against a hostile world - where sunlight shatters your DNA and every breath contains microbes that can kill.