In the midst of a chaotic evening in London's posh neighborhood of Mayfair, Frank Sinatra finds himself at a crossroads. His reputation as a suave ladies' man has earned him the attention of Mario, his harried brother, who begs for his help.

Desperate to escape the bohemian lifestyle that's taken over his life, Frank agrees to marry a sensible woman named Jane. But there's one condition: he must leave his carefree days behind and become a respectable gentleman.

As they navigate their complicated relationships and romantic entanglements, they encounter Tony, a charming but troubled young man who's struggling to find his place in the world. Will Frank choose to follow his heart or his head, and will Jane be able to bring order and stability into his life? The outcome is far from certain as this intriguing tale of love, loss, and self-discovery unfolds.