Phineas and Ferb Episode 2.40 Brain Drain

Phineas, Ferb, Isabella, and Baljeet all fall ill and are forced to stay in bed for the day (Buford also decides to remain in bed, but only because he's being lazy, not sick). To pass the time, the kids create a new battle video game that lets them play as themselves against each other. Meanwhile, Dr. Doofenshmirtz creates a helmet that enables him to control Perry's every action. But with crossed wiring and an electric surge, the kids are tuned into the helmet and control Agent P themselves, making them believe their game has reached the "Perry level", which enables him to battle Doofenshmirtz at the junkyard, where Vanessa is having a party with her fellow goths.