Carry on Cabby (1963)

Speedee Taxis is a great success, which means its workaholic owner Charlie starts neglecting Peggy, his wife. Suddenly a fleet of rival taxis appears from nowhere and start pinching all the fares. The rivals are Glamcabs, and they have a secret weapon: all their drivers are very attractive women. Who's behind Glamcabs? It's open warfare and only one fleet can survive.