The Coolest Coaster Ever is the name Phineas and Ferb gave to their roller coaster they constructed for an early Big Idea. Like the name suggests, it is a huge roller coaster that goes around the whole city. Agent P lifts the coaster in the air with a helicopter as part of trying to complete his mission, and after it is set down again, the coaster goes off course to places like Mount Rushmore, Paris, a Mr. Slushy Burger and outer space, by a satellite.