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 MIB's untarnished mission statement – protecting Earth from the scum of the universe. It's been four years since the alien-seeking agents averted an intergalactic disaster of epic proportions. Now it's a race against the clock as Jay must convince Kay – who not only has absolutely no memory of his time spent with the MIB, but is also the only living person left with the expertise to save the galaxy – to reunite with the MIB before the earth submits to ultimate destruction.
When an asteroid threatens to collide with Earth, NASA honcho Dan Truman determines the only way to stop it is to drill into its surface and detonate a nuclear bomb. This leads him to renowned driller Harry Stamper, who agrees to helm the dangerous space mission provided he can bring along his own hotshot crew. Among them is the cocksure A.J. who Harry thinks isn't good enough for his daughter, until the mission proves otherwise.
In order to foil a terrorist plot, an FBI agent undergoes facial transplant surgery and assumes the identity of a criminal mastermind. The plan turns sour when the criminal wakes up prematurely and seeks revenge.
