Simon travels the length of California, scaling one of the tallest trees on the planet and meeting the Hotshot fire crews battling blazes that are ravaging a state with a changing climate and a chronic shortage of water.
Not far from the celebrity-spotting tours of Beverley Hills, Simon meets the street doctors who provide help among the shocking poverty of Los Angeles' Skid Row.
Deep in the southern desert, he enters the Mad Max world of Americans who have dropped out of the rat race entirely and now live in the wild squat called Slab City.