O.W.C.A. Files, on Disney XD & Disney Channel
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streaming sites: Amazon; Disney+ (s4e32-33); Google Play; YouTube

This hour-long special is a spin-off of Phineas and Ferb (and potential back-door pilot for a series that didn't get picked up). It aired in November 2015 on Disney XD (about five months after the series originally ended), and January 2016 on Disney Channel. I didn't see it until May 2025, on Disney+. I thought it was reasonably fun and amusing, but not nearly as great as the series normally was.

Perry the Platypus is training a new group of prospective OWCA agents, including Harry the Hyena, Maggie the Macaw, Karen the Cat, and Heinz Doofenshmirtz the Ocelot. (He's so considered because he was raised by ocelots. And he's training to be an OWCA agents because he had given up evil at the end of the series.) But Perry and Carl are not satisfied with their progress. Meanwhile, all the other OWCA agents become infected with robotic fleas, which were sent by someone named Professor Parenthesis (voiced by Paul Reubens), who has a long-standing grudge against Major Monogram (who has no idea who he is). The robotic fleas put all the agents under Parenthesis's control, and he turns them against Monogram and Carl. So it's up to Perry and his team of trainees to rescue them and thwart Parenthesis's plan. Meanwhile, there's a trio of bugs named Napoleon, Wendell, and Floyd, who want to become OWCA agents, but they're so small that no one notices them. They go on an ill-fated quest to get noticed. And I guess there's nothing more to say. I don't really want to give away any specific details, beyond the basic premise that I've described. But there is a happy ending, of course.