Figueres and Rivett-Carnac lay out two 2050 scenarios, one of unbridled climate collapse, the other of a regenerative, zero carbon world, and argues that today’s choices will lock in which future we get. Figueres and Rivett-Carnac draw on their Paris Agreement experience to call for three mindset shifts, stubborn optimism, endless abundance and radical regeneration, and then walk through ten concrete actions, ranging from ditching fossil fuels and reforesting the Earth to defending truth engaging politically, and embracing a citizen, not consumer, identity. The authors stress that the window for meaningful change is closing fast, but it is still open. The book is both a warning and a call to action, grounded in science but driven by hope.