It's December 2011 in San Francisco. Bastian Lehmann is getting ready to launch his courier app, Postmates. But when he and his co-founders discover people want food delivered, not objects, they pivot to a business already cornered by Grubhub. Meanwhile, 30 miles away in Palo Alto, a business school student called Tony Xu is trying to figure out how to help a small macaroon shop fulfill delivery orders. His solution? DoorDash. Along with UberEats and Postmates, it will help pioneer the gig economy—and change the restaurant business forever.