S1·E7 Go Snow Part 4

Simon has frozen poor Underdog solid. All efforts to defrost Underdog fail. Somehow, Underdog defrosts himself and immediately flies around Simon and Cad so fast the two villains get dizzy. They fall down unconscious and are turned over to the law. Underdog then rescues the frozen people by using his super-hot atomic breath, defrosting them all in seconds. The episode ends with a group of people on the street saying "It's a plane," "It's a bird," "It's a frog!" & a man saying "A frog?" with Underdog saying: "Not plane, nor bird or even frog, it's just little old me, Underdog." before crashing into a building.