Agent J must travel back in time to MIB's early years in the 1960s and save his partner, Agent K, from being assassinated by an alien. Along the way, Agent J teams up with young Agent K and learns that there are secrets to the universe that Agent K never told him.
Four years after agents J and K averted an intergalactic disaster J is still working for the MIB while K has returned to the comforts of civilian life. While investigating a seemingly routine crime, J uncovers a diabolical plot masterminded by Serleena, an evil Kylothian monster who disguises herself as a sexy lingerie model. It's a race against the clock as J must find and convince K--who not only has no memory of his time spent with the agency,...