Networking technology has radically changed how we do many things — including startling other people. The group Improv Everywhere uses it to pull off pranks — or, as they call them, missions. Two of their best known missions are the famous annual no-pants subway ride, and the Grand Central Station freeze. Now the Improv Everywhere guys have a book, Causing a Scene: Extraordinary Pranks in Ordinary Places with Improv Everywhere. It's part a documentation of their work, part a how-to manual. Co-author Alex Scordelis joins The Takeaway to discuss the group and its methods.