|Reese Witherspoon||Susan Murphy / Ginormica|
|Hugh Laurie||Dr. Cockroach Ph.D.|
|Will Arnett||The Missing Link|
|Kiefer Sutherland||General W.R. Monger|
|Stephen Colbert||The President of the United States|
When a meteor full of space gunk transforms Susan Murphy into a giant, the government renames her Ginormica and confines her to a secret compound with other monsters, like bug-headed Dr. Cockroach . When an extraterrestrial robot lands on Earth and begins a rampage, Gen. W.R. Monger persuades the president to send Ginormica and her fellow monsters to battle the machine and save the planet.