 A young man (Allan Lane) wants to go to the south seas on a scientific expedition but his rich father won t finance it unless the young man agrees to work for one month in his father s dairy delivery milk. The agreement is that he can t make one single mistake (be late, miss a delivery, etc.) or the deal is off. The son begins his route and runs into a young lady (Joan Fontaine) who he mistakes for a maid (but who in actuality is of the uppercrust that just happens to be a bit down on her luck due to a over spending mother). They begin dating (each thinking the other is not what they are). They fall in love and when the young man climbs her balcony to propose her mother calls the police and he s thrown in jail. With his being in jail he won t be able to do his milk run and will thereby forfeit the bet with his father. The young woman assumes his position and does his milk route. In the meantime, he s released from jail and upon finding out his girl is doing his milk route goes to meet up with her. But unknown to either of them her mother thinks she was kidnaped by the milkman (boyfriend) when the REAL maid sees her leaving at night with the milkman s friend (who takes her to help with the milk route). Now the police are after all the milk trucks in the neighborhood -- looking for the kidnaper and his "victim". With cops hot on their bumper they manage to get to the dairy before his punch-out time and wins the bet! The south seas expedition turns into a south seas honeymoon!