Episode two continues to follow the incredible journey focusing on the middle months of our time in the womb when we become unique individuals. For the first ten weeks of pregnancy our biological sex is hidden. Meet the remarkable village of people in the Dominican Republic where the sex determination process in the womb doesn't always run to plan.Testosterone also influences the mind, which Michael sees when he meets a family in California, whose daughter, seven-year-old Mati, feels she has been born in the wrong body. Occasionally, our cells do not always follow the plan, like with baby Oliver, one of the 1 in 1000 babies who arrive with a cleft lip; or Cheryl, a member of just a handful of families in the world who have no fingerprints; and Jo, who is searching for her immune system twin as her best hope to overcome leukemia.