Upon her banking executive father, Lord Jimmy Broadbent (Sir Rex Harrison) remarrying who is now the second Lady Broadbent, Sheila (Kay Kendall), seventeen-year-old Jane Broadbent (Sandra Dee), who has been living in the States with her American mother since the divorce, pays her father in London a visit so that she can meet Sheila. Jane's visit coincides with it being "the season" in London: when all the society debutantes hold their balls to "come out" as being ready to find a suitable mate and marry. Sheila, as her first act of being Jane's British stepmother, wants Jane to come out along with all her British peers. Sheila believes that someone like if not David Fenner (Peter Myers) himself, he a guard at Buckingham Palace, would be a suitable mate for Jane. In attending some of the earlier season balls, Jane not only finds David Fenner a drip, but she also does not want to step on the toes of her first true friend in London, Clarissa Claremont (Diane Clare), who is in love with Fenner. Fenner, in turn, doesn't seem to know that Clarissa as a potential mate even exists while he sets his sights on Jane. That doesn't stop Clarissa's scheming mother, Mabel Claremont (Dame Angela Lansbury), from preventing anything from happening between Fenner and Jane so that Clarissa can end up with Fenner. Instead, Jane seems to be falling for twenty-three-year-old David Parkson (John Saxon), an Italian-American working as a drummer, his band playing at many of the social events among this circle. It isn't so much that he is a drummer, but Sheila buys into the rumors of David Parkson having been untoward to fellow deb Brenda Bassington in viewing him as unsuitable courting material for Jane. While he does what he needs to to appease his wife, Jimmy can see beyond the rumors eventually to get to the truth, specifically when he learns that Jane and Parkson, who he truly likes, are indeed in love. Jimmy has to find a way to make Sheila see the truth about Parkson, just telling her which he knows will not do the trick.