Sam Bissell works in the art department of a San Francisco advertising agency, but feels that his career is going nowhere after working in the same low-level job for six years without a promotion. He lives in a suburban home with his loving wife, Min, and their two young daughters.
At the agency, an extremely important client, puritanical dairy tycoon Simon Nurdlinger, demands that an upstanding "family man" represent his advertising account, or else he will take his business elsewhere. Since Sam is the only employee who qualifies, his boss, Mr. Burke, introduces Mr. Nurdlinger to Sam. Mr. Nurdlinger is impressed by Sam's wholesome approach and hires him as his account executive. When Sam goes home to celebrate, he meets Min's longtime friend and their new next-door neighbor, Janet Lagerlof, and they all go out to dinner together to celebrate his promotion and Janet's new home.
Janet, a beautiful woman, is recently divorced from her husband Howard Ebbets and is happier than ever. She has also come into a $15million inheritance from her grandfather, though his will stipulates that she must be happily married in order to receive the inheritance. California law dictates that a divorce is not final until a year from final settlement. Since only six months have passed, Janet decides to hide the divorce from her cousins Irene and Jack, who stand to inherit if Janet is disqualified. When Irene and Jack arrive for a surprise visit, Janet introduces Sam as her husband. Although they have never met Howard, Irene and Jack remain suspicious of Janet.
At Min's suggestion, Janet drives Sam to work to avoid suspicion. There, Sam introduces Janet as his wife to Mr. Burke and Mr. Nurdlinger, who invites Sam and Janet to a dinner party at his home. When Irene and Jack hire a private investigator to watch the couple from a fake vacuum cleaner truck parked opposite their houses, Sam and Janet are forced to continue the charade over the next few days, with Sam sneaking back and forth between his house and Janet's. Despite Min's complicity, she soon becomes jealous of Sam and Janet.
While Sam is sleeping over at Janet's house one night, Howard sneaks in and attempts a reconciliation with Janet, who refuses. With the private investigator still parked outside, Howard is forced to pose as Min's husband, arousing the jealousy of both Sam and Janet. The day before the probate court to settle the distribution of the Lagerlof will, Sam panics when he finds that Nurdlinger billboards have been erected all over the city with pictures of him and Janet, identifying them as "Mr. and Mrs. Sam Bissell". Since Janet risks losing the inheritance, she and Sam stay up all night defacing the billboards, even though Min, feeling that the charade has gone too far, threatens to leave Sam.
To access the final billboard, Sam rents a room in a cheap hotel, unaware that it is frequented by prostitutes. A prostitute enters Sam's room, but when she sees him carrying paint cans and a paintbrush, she flees the room screaming for help. Sam chases her through the hotel, trying to explain himself, until Janet arrives and defuses the situation by telling the desk clerk and the prostitute that Sam is a famous painter who merely checked into the hotel to paint.
The next day, Janet and Howard argue as she accuses him of only wanting her back because of her inheritance money, but they eventually agree to rekindle their relationship. Sam returns home and reconciles with Min.
↑Levine, Ken (December 20, 2008). "Jim Fritzell & Everett Greenbaum". By Ken Levine. Retrieved November 15, 2014. Everett [Greenbaum]... built bizarre sculptures out of pipes and everyday items. (they're [sic] featured in GOOD NEIGHBOR SAM...)
