Sam (MATTHEW BRODERICK), an astronomer from a small town in the midwest, is a naive romantic. Maggie (MEG RYAN), a photographer and collage artist from New York, is a worldly-wise cynic. Strangers and polar opposites, what they have in common is an obsession with the respective lovers who’ve just jilted them and are now blissfully sharing a romantic apartment in Soho. Sam will do anything to win back Linda (KELLY PRESTON), his childhood sweetheart and only love. Maggie will do anything to get revenge on Anton (TCHEKY KARYO), her charming, accomplished French lover and ex-fiance. So when Sam and Maggie encounter each other in New York, each spying on the same “love nest,” each watching the romance unfolding there with envy and rage, an unlikely alliance is formed. Soon, Maggie convinces a reluctant Sam that the only way to get Linda back is to humiliate Anton and destroy his life. As Linda and Anton, blissfully unaware, pursue their romance, Sam and Maggie embark on a diabolically funny scheme of infiltration and revenge. Yet their plans unexpectedly begin going awry as the relationships between the four characters evolve in ways none of them could ever have imagined.
