This is an episode of Phineas and Ferb where first Coop, from Kid VS Kat has been on their rides and he wants to meet them face to face. Meanwhile, Phineas and Ferb have nothing to do that day. Later Perry swipes his hat on and goes to his lair and finds out he has an alien mutant (Kat) in Phineas and Ferb's backyard becuase Coop gets there. Then Coop talks to Phineas and Ferb about how Kat is an alien from another planet and how he trys to get it in trouble. Candace hears Coop say that and asks Phineas and Ferb if she can talk to Coop. At Doofenshmirtz Evil Inc, Doof also has nothing to do that day so he uses his old Retireinator (the one for when he stops working). So Doof then remembers that Perry didn't return Norm yet so he goes out to find Norm. When Perry gets to the backyard with