A shooting star falls from Outer Space towards the Hundred Acre Wood. Winnie the Pooh, Darby, Roo, Lumpy, Buster and Tigger are out in the Hundred Acre Wood one night, playing flashlight tag with the fireflies. They see the shooting star fall to the wood, but are too sleepy to go look for it. The shooting star (or space rock) lands in Rabbit's garden and begins to put its effect on it. The next morning, the Super Sleuths get a call from Rabbit who claims his vegetables are giant. They discover the space rock and eat these giant vegetables and get super powers. Tigger becomes super strong after eating giant spinach, Pooh gets super sight after eating a giant carrot, Buster can dig super fast after eating a giant potato, and Darby can fly after eating a giant celery. They make new costumes and continue to help others around the wood with their new superpowers. Lumpy and Roo were soon trapped on an island and a large boulder is blocking the way out. Their mothers call the Super Sleuths (who now call themselves the Super Duper Super Sleuths) to help find them. Meanwhile, Rabbit hosts a festival to show everyone what the space rock can do. The Super Duper Super Sleuths come across the Rather Impossible to Cross Cliff that's too high for jumping but they come up with a way to get down by making a slide out of a log. While Rabbit prepares to make another vegetable grow, the rock suddenly stops glowing which also loses its powers. Also, the giant vegetables began shrinking back to their normal sizes which makes Rabbit realize that this could also mean no more superpowers so he races off to warn the Super Sleuths. Rabbit shows up to deliver the news just as Tigger tries to remove the boulder but fails when his super strength wear off. The Super Sleuths then realize that their superpowers were gone, but they were able to figure out an idea by making a pulley system out of the wheels of their scooters and the vines that Darby saw earlier to lift up the boulder long enough for Lumpy and Roo to get across. After rescuing them, all is well as they go back to being normal Super Sleuths.
The special was edited for syndication and for release on streaming on Disney+. The story was split into two separate episodes: "Super Duper Super Sleuths Part 1" and "Super Duper Super Sleuths Part 2." Additionally, the story is split into four chapters, with the on-screen chapter titles narrated by Darby.