When Bill and Jean hire an au pair for their children they have no idea the effect she will have on their sex lives. Bill is strongly attracted to the uninhibited, thoroughly desirable French girl, and succumbs to temptation. Jean, now sexually awakened, proves an exciting challenge to her and eventually achieves a lesbian fulfilment. Her new, intense sexual desire is a revelation to Bill, and the complex situation is uniquely resolved by an unusually satisfying `ménage à trois` relationship.