Abby Nakajima and Derek Hoyle snuck into the lab of Dr. Gustavus to attempt to find out what he was working on. They encountered several of the mutated specimens of Dr. Gustavus, including a Leaellynosaura that had been genetically modified for heightened intelligence and dexterity. As Gustavus threatened Abby and Derek with a machine gun, Gideon leaped for his pistol that he had dropped earlier. Turning, he had his claw on the trigger, and Abby attempted to coax him into not pressing it. When Gustavus began to threaten the animal not to give over the gun, the frightened Dinosaur shot Gustavus in the chest. When the shed fell into the ocean, Gideon along with the other mutated Dinosaurs, drowned.