At Belpher Castle, the Earl tends his roses, and writes the family history in as desultory a manner as he can -- his secretary Alice keeps getting on his case. Meanwhile, his sister is trying to keep his daughter Maud captive in the castle, in hopes that she will forget the young American she met in Wales, and marry the sister's stepson Reggie, who is in love with Alice.
This being P. G. Wodehouse, things don't stay that simple. Reggie helps Maud get to London, because she has read in the newspaper about her beloved's uncle returning there, which means her beloved must be there. She stumbles across her brother Percy, who supports his aunt. She dives into the nearest taxi to hide. George Bevan, composer of music for popular plays, gallantly helps conceal this damsel -- among other things, destroying Percy's hat -- and falls in love with first sight.
It gets more complex from there. There's Billie, in Bevan's play, who regales him with tales of the latest show girl getting her heart broken in romance; there's tours of Belpher Castle; the servants gamble on who Maud will marry after a house party; locals mistake George for an artist and Percy for a tramp; Percy turns twenty-one and a ball is held for it, at which he does not dance, but thinks he recognizes a servant; an elopement that comes off, and one that doesn't, and one secret marriage.
Being Wodehouse, you know all the threads will be tied up. It's watching them in progress that so amazing.