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At a scientific demonstration, Dr. Norton shows off his latest invention, a diminishing ray capable of shrinking and enlarging any object. The device is tested on a lion which is shrunken down in front of the press. Norton announces that the lion will later be restored to its normal size at the International Inventor's Convention. Shortly after the demonstration however, the janitor announces himself as a super- villain known as the Gadgeteer, and steals the shrinking ray. Since Peter was taking photos of the demonstration, it isn't long before Spidey shows up to try and prevent the device's theft. During their battle, Spider-Man is shrunk down in size to two inches tall, and the Gadgeteer escapes with the ray. Now with a new perspective on the world, Spidey attempts to phone Aunt May to tell her that he will be busy this afternoon, but fails since his voice isn't loud enough to be heard over the phone. Instead, he decides to type a letter explaining his absence at the Bugle, where he is reminded that the Inventor's Convention is in town, complete with a new futuristic micro-chip computer on display there. Spidey concludes that the Gadgeteer is certain to show up, after the computer. Gadgeteer does indeed wish to steal the micro-chip, and shrinks himself to get at it. He encounters Spidey there, and they battle. Afterwards, Spidey discovers that he has shrunk down further in size to only being half an inch tall. Spidey fights further with the Gadgeteer, trying to get access to the diminishing ray before he shrinks to nothing.
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The Hulk faced a similar scenario in the 1982 Incredible Hulk cartoon (from Marvel Productions) episode titled "The Incredible Shrinking Hulk".