While Algernon rushes out to make christening arrangements, Cecily writes Ernest’s proposal in her diary. She is interrupted by Merriman announcing The Honorable Gwendolen Fairfax to see Jack; unfortunately, Jack is at the rectory. Cecily asks her in, and they introduce themselves. Gwendolen did not know Jack had a ward, and she wishes Cecily were older and less beautiful.
Both announce that they are engaged to Ernest Worthing. When they compare diaries, they decide that Gwendolen was asked first; however, Cecily says that since then, he has obviously changed his mind and proposed to Cecily. Merriman and a footman enter with tea, which stops their argument. They discuss geography and flowers in a civilized manner while the servants are present. However, during the tea ceremony, Cecily deliberately gives Gwendolen sugar in her tea when Gwendolen did not want sugar and tea cake when Gwendolen expressly asked for bread and butter. The situation is very tense and strained.
Jack arrives, and Gwendolen calls him Ernest; he kisses Gwendolen who demands an explanation of the situation. Cecily explains that this is not Ernest but her guardian, Jack Worthing. Algernon comes in, and Cecily calls him Ernest. Gwendolen explains that he is her cousin, Algernon Moncrieff. The ladies then console each other because the men have played a monstrous trick on them. Jack sheepishly admits that he has no brother Ernest and has never had a brother of any kind. Both ladies announce that they are not engaged to anyone and leave to go into the house.
