Will & Grace are best friends. Will is a gay lawyer and Grace is a straight interior designer. They both live in New York. Grace is engaged to a real jerk, but when that relationship falls apart, she moves in with Will. This is only supposed to be until Grace finds a place of her own, but she and Will end up with each other as permanent roommates. Also in the cast are Jack, Will's flamboyant gay friend and Karen, Graces' secretary/assistant who doesn't really need to work because she married money several times.

　　A group of aliens has come to Earth to learn about its population, customs, etc. To avoid detection, they have taken on human form which gives them human emotions, physical needs etc. WITHOUT the understanding of what they mean or the inhibitions normally present in humans. Their leader takes the position of a college professor, their military expert as his sister, their intelligence expert, supposedly oldest of group takes form of his teenage son. The uninhibited reactions turn everyday events into unusual situations.