If your body carried a deadly gene that increased your chances of getting breast cancer to 80 percent - would you want to know? This poignant one-hour documentary follows 18-year-old Josie Bellerby, a gorgeous, fun-loving, typical teenager except for one thing: Her mum carries a hereditary gene that has cursed their family for generations, killing her great-grandmother and her mother. There is a test that tells you if you have the gene. Josie's Mum Julia was one of the first in the UK to take it a few years ago. She proved positive, and decided to have drastic surgery - to remove both her breasts. Now Josie and her two sisters face the same heartbreaking choice. Big sister Lucy has decided she's ready to take the test and will soon receive life-changing news. Josie has a dilemma should she find out if she has it too? Her family thinks she's too young to know, she should be enjoying her young life not worrying about the risk of cancer and a double mastectomy.