For Dan Gallagher, life is good. He is on the rise at his New York law firm, is happily married to his wife, Beth, and has a loving daughter. But, after a casual fling with a sultry book editor named Alex, everything changes. Jilted by Dan, Alex becomes unstable, her behavior escalating from aggressive pursuit to obsessive stalking. Dan realizes that his main problem is not hiding his affair, but rather saving himself and his family.
After one short blind date, Mary Horowitz, a brilliant and eccentric crossword constructor, is convinced that Steve, a CCN cameraman, is her soul mate. Because his job takes him hither and yon, she crisscrosses the country following Steve, with the encouragement of a reporter, turning up at media events he's at to convince him they are perfect for each other. Along the way, she befriends an assortment of misfits who accept her for who she is, leading her to reassess her reasons for this strange journey.
Newly married couple, Greg and Joy Lawson, move into their home in the suburbs and are warmly welcomed by their neighbors, one of whom, Becky, takes a dangerous interest in Greg. While Joy is away, they spend an intimate moment together, orchestrated by Becky, and then they agree to keep their distance. But she inserts herself into every aspect of his life, wreaking havoc on his marriage and potential job until the final explosive confrontation.
As she reaches her mid-thirties and quits her lucrative job, singleton Olivia finds herself unsure about her future and her relationships with her successful and wealthy friends. She begins to envy the security of her richer friends and, although their lives may seem easier, Olivia's friends have their problems too: screenwriters Christine and Patrick are unable to collaborate on their latest project, Jane and Aaron have lost the romance in their relationship, and Franny and Matt have difficulties handling the demands of parenthood.