At the end of Sonic the Hedgehog 2, the evil Dr. Robotnik had his Death Egg downed from orbit by the heroes, Sonic the Hedgehog and his companion Miles "Tails" Prower. Having not been completely destroyed after all, the Death Egg has crash-landed on the Floating Island, taking it to the ocean below. This island has special properties - not least of which being its eponymous power of magical suspension. When Dr. Robotnik detects the presence of a massive Chaos Emerald within the island's depths, he decides to once again seek out the Chaos Emeralds so that his fallen Death Egg can regain orbit in space. Turning his crushing defeat into a sleek advantage yet again, he kidnaps Animals to convert into Badniks and created a new line of weapons. Meanwhile, Knuckles is taking his usual walk along the Emerald altar to check if the Emeralds are alright, suddenly a huge earthquake came out of nowhere, Knuckles saw the Emeralds reverberating in mid-air, stunned, he was suddenly threw into the air before blacking out. When he woke up, the Chaos Emeralds were gone, but Knuckles also saw a huge egg in the distance, surprised, he then recalled a legend of an ancient dragon sent to destroy the world in the end times, thinking this mysterious egg to be the dragon he set out, and - A giant egg-shaped figure appeared out of nowhere, calling himself "Dr. Eggman", he explained to Knuckles he had come here to study this giant egg, and that an evil hedgehog named Sonic was trying to not only interfere with his research, but steal the Chaos Emeralds as well. Knuckles, duped by the doctor, ran off to find this miscreant. Eggman smiled at himself, pleased at his ability to lie.