 Fourth in a set of Nickelodeon series crossovers, it s science vs. magic as Timmy Turner (Tara Strong) who s destined to fail at science class wishes he had the greatest lab in the universe, which just happens to be the not-so-secret lab of Jimmy Neutron (Debi Derryberry). Timmy and Jimmy are teleported to Retroville and Dimmsdale respectivley, where Jimmy was planning to upgrade his mechanical dog Goddard, only to have Timmy download a video game that s far more violent than even it s manufacturers expected, and somehow wins the heart of Cindy Vortex (Carolyn Lawrence). Meanwhile, Jimmy s effort to return to Retroville has been thwarted by fairy-mad teacher Denzel Crocker (Carlos Alazraqui) who uses Jimmy s scientific knowhow to take over Fairy World.