Collects X-Men: First Class (2007) #1-9. More early adventures of the young X-Men! Cyclops, Marvel Girl, Angel, Beast and Iceman, Professor X's very first students at the Xavier School for Gifted Youngsters, taught the world what it meant to be X-Men - and heroes. And these are the hidden stories of the team that laid the foundation of a mutant dynasty! Featuring a visit from the Fantastic Four's Invisible Girl, a mission to Monster Island and a vacation road trip Hank and Bobby style! But when the mutant-hunting Sentinels set their sights on Quicksilver and the Scarlet Witch, can the depowered X-Men save their friends from extermination? Plus: The fledgling heroes encounter shape-shifting Skrulls from outer space, the swamp-dwelling creature called the Man-Thing and the super-spy known as Black Widow! And Marvel Girl and the Scarlet Witch become besties while battling the Mole Man and more!