A serial monogamist named Selena is suspected of marrying rich men and then killing them off, so Peter and Neal must go undercover as bachelors at a charity auction, hoping that one of them will catch her eye. Peter manages to win Selena, much to Elizabeth's concern and disappointment.
Peter has to string Selena along, however, as he tries to win her heart as well as a marriage proposal. Meanwhile, Neal and Sara realize that as Peter and Elizabeth's relationship is being tested, they haven't even been on a real date.
Neal and Sara's romantic evening has to be commandeered by Peter, however, as he gets closer to Selena. Everything gets resolved, and Peter and Elizabeth end up having the intimate wedding they couldn't get before.