The Girl in the Taxi.

In this British musical, set in Paris, an apparently upstanding husband and father spends his nights fooling around with wild women. His son, wanting to be just like his dad, begins dating a seductive widow--the same widow his father has been seeing. Trouble ensues when the father refuses to let his daughter marry her true love. When the fiancée learns of the father-son shenanigans, he begins blackmailing them into letting him marry the daughter.