故事從超級壞蛋Megamind（Will Ferrell 配音）和超級英雄城市超人Metroman（Brad Pitt 配音）的童年時代講起，從尚在襁褓之時起他們就結下了樑子，開始了誰也不服誰的生涯（顯然在惡搞《超人》）。一個要代表正義，一個就硬要邪惡。在故事其後的發展中，邪惡戰勝了正義，超級壞蛋Megamind打敗了超級英雄Metroman。然後，他卻發現沒有了對手的日子相當寂寞，於是，Megamind自己造了一個超級英雄Titan（Jonah Hill 配音）出來。可鬱悶的是，新英雄的夢想卻是做一個超級大惡人。而此時，女記者羅克珊（Tina Fey 配音）站出來對眾人說：當我們說收到威脅的時候誰會站在我們身邊？誰能前來保護無辜者？答案是：Megamind。這下超級大壞蛋更鬱悶了……

A crew of interplanetary archaeologists is threatened when an alien creature impregnates one of their members, causing her to turn homicidal and murder them one by one.

An unsuspecting woman is impregnated by aliens who are experimenting on the human population.

Jerry is a strange and solitary boy who lives with his young neglectful mother in a run down apartment. He spends his weekends hidden away in his bedroom making model figurines and watching TV alone. While investigating a damp stain on his bedroom wall, Jerry peels off some wallpaper, revealing a seductive alien orifice growing behind the plaster. After spending an ever increasing amount of time in his bedroom exploring and inspecting the alien creature, Jerry embarks on his first sexual experience. After numerous encounters between Jerry and the creature, it becomes pregnant. Filled with panic and guilt, Jerry attempts to abort the alien creature, leading to a horrific outcome which neither himself nor his mother will ever forget.