Previously, in Lady Windermere's Fan...
Lord Darlington visits Lady Windermere. We learn that it is Lady Windermere's 21st birthday and that she will be giving a party that evening. Her husband has given her a fan as a birthday present. It has her name (Margaret) on it. Lord Darlington flirts with Lady Windermere, but Lady Windermere rejects his attempts at flirtation.