Larry and Kitty are two middle-class suburbanites who find themselves growing bored with their lives and respective marriages. Although each always found the other grating in manner, they find themselves falling in love when thrown together without their spouses on a vacation. After returning home, they try to break things off, but always seem to grow closer. A holiday together will finally settle whether they should end their marriages.
One night on a lonely highway, a speeding car tosses a satchel of money, meant for somebody else, into Jane and Alan Palmer's back seat. Alan wants to turn it over to the police, but Jane, with luxury within her reach, persuades him to hang onto it "for a while." Soon, the Palmers are traced by one Danny Fuller, a sleazy character who claims the money is his. To hang onto it, Jane will need all the qualities of an ultimate femme fatale...and does she ever have them!