Sontag referenced this play in her Notes on Camp (“I adore simple pleasures, they are the last refuge of the complex”). It’s an amusing four act play with lots of zingers. “Men marry because they are tired; women because they are curious. Both are disappointed.” And: “The happiness of a married man depends on the people he has not married.”
Act 1 ends with Lord Illingworth noticing the handwriting of a letter and saying it reminded him of a lady he once knew, but when pressed he called her a woman of no importance. This turns out to be the mother of Gerald, whom Illingworth just hired to be his secretary, and who of course was Illingworth’s mistress, making Illingworth Gerald’s father. In the end, Mrs Arbuthnot has her revenge, rejecting Ill’s plea for marriage and noting the glove that she slapped him with as that from a visitor, a man of no importance.