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 the president of Russia suddenly dies, a man whose politics are virtually unknown succeeds him. The change in political leaders sparks paranoia among American CIA officials, so CIA director Bill Cabot recruits a young analyst to supply insight and advice on the situation. Then the unthinkable happens: a nuclear bomb explodes in a U.S. city, and America is quick to blame the Russians.

Cynical bodyguard Jericho is hired by a man possessed by Satan, who is in search of his bride. When Jericho realizes what is happening, he must do everything he can to save the woman and the world.