Upstairs and Down (1919)

Alice Chesterton is described as a "Baby Vamp" by the social set and engaged to boring Tom Carey. She flirts with many of the male guests idling at the Ives' Long Island house party, then encourages Terence O'Keefe, a playboy polo player from Ireland, to rendezvous with her in the city; they are seen together at the "Midnight Frolic". Because of this, Mrs. Ives convinces Alice's newly-arrived sister Betty to look after Alice.