Gumball inadvertently cracks open Penny’s shell and discovers who she really is inside…
While performing a school play,
Gumball is so nervous about kissing Penny that he accidentally headbutts her and cracks open her shell.
They discover that under Penny's shell is an emotional shape-shifting inner self.
Penny's father is determined for Penny to keep it hidden but Gumball encourages her to show the world who, or what, she really is…
Note: Gumball & Penny Start Dating.