Emma is in "an exquisite flutter of happiness" as they sit down to tea Mr. Woodhouse contentedly unaware of "the impending evil" of the engagement. The night is sleepless for her as she considers what must be done about her father and Harriet and decides that, while her father lives, she and George can be only engaged. In determining how least to be Harriet's "enemy," she decides to communicate with her only by letter and to get her an invitation to visit the John Knightleys in London. After she sadly writes the letter early the next morning, George comes for breakfast and has hardly left when a thick letter arrives from Randalls, containing a long explanatory letter from Frank to Mrs. Weston. It is a good and believable letter which, in Emma's present state of mind and heart, mostly exonerates Frank for his past actions in Highbury. Among other explanations, he says that he felt that Emma had guessed the truth about him and Jane and that at the end of his first visit he had almost confessed the truth to her. He also discloses that it was he who sent Jane the pianoforte. He has nothing but good words for Emma. For himself he expresses both justification and regret.
Because of the letter, Emma's former regard for the writer returns and she desires George to read the letter also. As he does, he occasionally makes a comment and concludes by feeling better about Frank. Then he turns to the problem of Mr. Woodhouse. The only way he can see to ask her to marry him without "attacking the happiness of her father" is for himself to come and live at Hartfield. She promises to think it over, and the proposition becomes more and more reasonable as she dwells upon it. But there is still the problem of Harriet, who is hardly likely to find in time that George is less worthy of worship than Mr. Elton was found to be. And it is really "too much to hope even of Harriet, that she could be in love with more than three men in one year."
The emphasis in these chapters is upon clearing up matters in regard to Frank, and this is done primarily through his letter and the reaction to it by Emma and George. One sidelight to George's reading the letter is the forecast of what the domestic situation will be for him and Emma: It will obviously be comfortable and lively, a true meeting of minds and hearts with just enough difference thrown in for interesting variety. While an answer is found to the problem of Mr. Woodhouse as an obstacle to marriage, Emma's private problem of Harriet, of whose affection for him George knows nothing, continues. Superb novelist as she is, Miss Austen keeps a suspenseful facet of the plot developing to help support the leisureliness of her exploratory denouement. At the end of Chapter XV there is a faint and almost nostalgic echo of Emma's original willful desire to maneuver someone into marriage when she thinks it is too much to hope Harriet could love three men in one year.