Tuck Pendleton is a fictional character from the 1987 science fiction film, Innerspace. He is a test pilot who volunteers for a miniaturization experiment, where he is shrunk down and injected into the body of a hypochondriac grocery store clerk named Jack Putter. As Tuck navigates the human body, he must communicate with Jack to complete his mission and return to normal size. The film combines elements of adventure and comedy, showcasing Tuck's resourcefulness and bravery in a unique and challenging situation.