Snapped: Killer Couples (2013)

S1E16 Toy to the World

Seeing as a platypus doesn't have an active lifestyle, Phineas and Ferb decide to craft a wooden toy replica of Perry to market to a toy company. Meanwhile, the real Perry embarks on a mission to thwart Doofenshmirtz, who is attempting to construct the Great Wall of the Tri-State Area and set up toll booths at the sole exits.