So many of us believe that we are able to shape our own destiny. But what if free will doesn't exist? What if our lives are largely predetermined, and so-called choices are actually mandated by what's hardwired in our brains? Neuroscience is challenging what we know about ourselves, revealing how we make decisions and form our own reality. Unpacking some remarkable examples, Hannah Critchlow explains that pleasure receptors in our brains determine how much we eat, phobias can be transmitted through heredity, and we can sniff out ideal partners with genes that give our offspring the best chance of survival.