A Japanese Company funded by the USA experimenting with anti-bacteriological weapons creates a mutated humanoid rat creature which becomes violent and murders the lab technicians. The lab is condemned and its horrifying experiments kept a secret. However the strange bacteria leak from the lab and spreads to the nearby inhabitants causing a humanoid epidemic! Three people are sent to the lab to uncover the US government conspiracy that unleashed a bloodthirsty monster beyond their wildest imagination.
With the impending ice age almost upon them, a mismatched trio of prehistoric critters -- Manny the woolly mammoth, Diego the saber-toothed tiger and Sid the giant sloth -- find an orphaned infant and decide to return it to its human parents.
A rare mutation has occurred within the vampire community - The Reaper. A vampire so consumed with an insatiable bloodlust that they prey on vampires as well as humans, transforming victims who are unlucky enough to survive into Reapers themselves.
Kay and Jay reunite to provide our best, last and only line of defense against a sinister seductress who levels the toughest challenge yet to the MIBs untarnished mission statement: protecting the earth from the scum of the universe.