As climate breakdown begins, the question each of us must ask is: Do I really want to know the truth? Am I willing to face it? In this book Rupert Read argues compellingly that truthfulness on climate has surprising rewards: we get to live authentically, win or lose; to be with each other rather than stuck in individualised silos of anxiety; and, most important of all, to turn the difficult emotions which climate-honesty generates into energy. In a series of provocative and stimulating chapters, Read shows how truth is a mighty power that can mobilise untold millions. Read tackles in particular ‘the 1.5 delusion’ – the belief that it’s still practically possible for humanity to remain in the ‘safe’ space below 1.5°C of global over-heat. He suggests abandoning this fantasy makes visible the terrible injustice being perpetrated upon the global South and on our children, and that radical truth-telling will liberate us to transformatively adapt to our future on a changed planet. This book is for anyone and everyone who cares.