Watch Phineas and Ferb on Disney XD Catch all of Phineas and Ferb s Greatest Musical hits Phineas and Ferb invent, scheme, and stay one step ahead of their sister Candace who just wants to catch them up to no good Their pet platypus Perry lives a double life as a secret agent whose sole mission is to foil Dr. Doofenshmirtz s plans. , phineasandferb, disneyxd