In an adventure that blends science fiction and comedy, a test pilot named Tuck Pendleton volunteers as a guinea pig for a revolutionary experiment: to be shrunk to microscopic size and injected into the body of a guinea pig. However, an unexpected attack by a rival gang causes chaos during the miniaturization phase. Instead of being part of the proper mission, Tuck ends up being injected into the body of a neurotic and clumsy inventor named Jack Putter, who unknowingly becomes embroiled in the madness of this adventure.
As Tuck navigates the intricate and thrilling world of the human body, he comes to discover that there is much more than meets the eye. From battles through blood vessels to facing off against a villain who wants to take over the project, every step is a mix of action and hilarity. Jack, desperate to get Tuck out of his peculiar situation, must find a way to help his new friend while also dealing with his own emotional issues and fears.
Featuring a colorful cast that includes Martin Short and Dennis Quaid, this film not only delivers laughs galore but also a good dose of action and adventure. As the plot unfolds, Tuck and Jack must learn to trust each other in order to survive the lurking dangers, proving that even in the strangest of places, friendship can flourish.