Men in Black II

Men in Black II (stylized as MIIB) is a 2002 American sci-fi action comedy starring Will Smith and Tommy Lee Jones as members of a secret agency that is tasked with monitoring, policing, and protecting alien lifeforms that secretly live on Earth. It is the first sequel to the 1997 movie Men in Black, also starring Smith and Jones. It costars Lara Flynn Boyle, Johnny Knoxville, Rosario Dawson, Tony Shalhoub, and Rip Torn. Both movies are based on the 1990 Aircel Comics comic book series.

Plot
Agent J (Smith) deals with a new alien threat that only Agent K (Jones) has the ability to handle. Unfortunately, Agent K retired at the end of the previous film; per Men in Black protocol, all retiring agents have their memories erased using a wand-like "neuralyzer." As Agent K's former (and last) partner, Agent J is tasked with finding him and restoring his memories before Serleena (Boyle), an alien disguised as a model, can find an artifact from the planet Zartha.

Jay, Kay, and their 'civilian' ally Laura (Dawson) defeat Serleena and return the 'artifact' (revealed to be Laura) to Zartha, saving both planets. Unfortunately, their final battle with Serleena takes places in the skies over New York City and is witnessed by thousands of people. Agent Kay reveals that MiB have planned for such a scenario; he activates the torch in the Statue of Liberty, which is revealed to be an enormous neuralyzer. The memory of the battle is successfully erased from everyone's minds.

Mission complete, Agent K decides to remain an agent, allowing Agent J to get his old partner back.