They are the best kept secret in the Universe. Working for a highly-funded yet unofficial government agency, 'K' (Tommy Lee Jones) and 'J' (Will Smith) are the Men in Black, providers of immigration services and regulators of all things alien on earth.  They are your best, last and only line of defence.  They work in secret and dress in black... they are the Men in Black - protecting the earth from the scum of the Universe...