S1, E1: Do You Really Want to Know? is a documentary about the complex emotional, ethical and psychological issues surrounding the new frontier of predictive genetic testing. It follows three families who have been confronted with the difficult decision of whether or not to be tested for Huntington's disease – a degenerative neurological illness that is akin to having ALS, Schizophrenia and Alzheimer's, and one of the first diseases people could be accurately and conclusively tested for, before the onset of any symptoms. As scientists discover more ways to identify diseases before we know we have them, "do you really want to know?" will be a question more and more of us will face.