Its from the Importance of being Earnest by Oscar Wilde
this bit will give you some idea
Jack himself wishes to marry Gwendolen, who is Algernon's cousin, but runs into a few problems. First, Gwendolen seems to love him only because she believes his name is Ernest, which she thinks is the most beautiful name in the world. Second, Gwendolen's mother is the terrifying Lady Bracknell. Lady Bracknell is horrified when she learns that Jack was adopted as a baby after being discovered in a handbag at a railway station. In her opinion it is absolutely below the standards of her daughter to "marry into a cloakroom and form an alliance with a parcel", as she puts it.
When she find out Lady Bracknell says "A HANDBAG!" It's the bit most people remember from the play