Tom and the others want to perform a play in the billiard room but Edmund is against it as their father, still absent, wouldn't care for it.

Henry decides to make a play for Fanny, whose brother William drops by on leave from the Navy, and, with both daughters gone, Sir Thomas throws a ball for Fanny.

Henry would marry Fanny. To this end he's seen to William's promotion in the Navy, but Fanny will have none of him.

As Fanny visits her parents, calamity befalls the Bertrams: Henry runs off with Maria, Tom lies sick with fever and abandoned by his friends, and Edmund glimpses Mary's true character.