Agent Jay (Will Smith), having grown lonely and angst-ridden as an MiB, uncovers a diabolical plot masterminded by Serleena (Lara Flynn Boyle), an evil Kylothian monster that disguises itself as a sexy lingerie model, when he’s called to a pizza joint to investigate alien activity. While there he meets Laura, a witness, and sparks fly between them. After some flirting, he decides not to neuralize her. When Serleena takes the entire MiB building hostage, there is only one person left for Jay to turn to � his former partner, Agent Kay (Tommy Lee Jones), who is now a drone in another large government office, the U.S. Postal Service. As the two agents track Serleena and try to save the planet, Laura’s past is revealed, as is the role she must play in stopping Serleena.