Twins Sophie and Tom buy a computer game called Saving Mythtopia to help them with their school project, but when they install it on their computer, strange things happen. The characters on the screen are disappearing! Next, the twins get smaller and smaller and are pulled through a portal into the world of Mythtopia, where everything is in chaos. The Titan King Cronus has escaped from prison and is changing the plots of some classic Greek myths. The twins must check the original stories on their phones and correct the errors Cronus has created. It is their job to save Mythtopia, but can they do it?