Tibby lives in his own world at Oxford, and he clearly doesn't like to be troubled by the lives of others. He's a classic academic, and though he's not a particularly bad person, he never descends from his ivory tower. At present, he's learning Chinese, and it's his principal pastime.
Helen turns up one day, after warning Tibby of her arrival with a telegram. She tells him about her adventure in Oniton, and tells him that she's not going back home to Wickham Place.
Tibby is more concerned with lunch than with his sister's troubles.
Helen goes on, saying that he's to tell Margaret that she just wants to be alone – she's going to Germany. As for the house, her siblings can do what they like about it.
Tibby asks if something happened at Evie's wedding, and Helen starts to cry. He doesn't want her to ruin his lunch, so he goes right on eating.
Helen pulls herself together, and brings up Mr. Wilcox, hinting ominously that he's done something terrible and ruined lives. She mentions the Basts, and Tibby is exasperated.
Tibby assumes correctly that this means that Mr. Wilcox has had a mistress, and Helen launches into an attack on Mr. Wilcox's behavior towards the Basts. She thinks it's his fault that they're paupers. She then explains the Leonard situation.
Tibby admits that it's a very unfortunate series of events. Helen wants him to decide what to do about this knowledge about Mr. Wilcox, but Tibby has no opinion on what to do about Margaret's involvement in all of this. He prefers to deal with people in books, not in person.
Helen has given up on stopping Margaret's marriage, but now she's worried about compensating the Basts for Mr. Wilcox's wrongs. She wants to give them five thousand pounds.
Tibby is taken aback, but his sister is determined to give them this huge sum, and she puts him in charge of doling it out.
Tibby walks his sister to the train station, and he is quite affected by her distress – at least, until he gets distracted by a statue on his way home.
The next day, Margaret and Tibby meet. She asks if Helen was upset about a rumor about Henry, and Tibby, thankful to be relieved of his duties, says yes.
He takes care of the second task Helen set to him by sending a check for the Basts, but it's returned with a civil note that says the money is not needed. Helen is upset, and insists that Tibby go back and force the money upon the Basts.
However, the Basts are nowhere to be found – they were evicted, and nobody knows where they went.
Helen, dismayed, isn't sure what to do with her money. She takes it out of her stocks, but, not knowing what to do, ends up reinvesting it and becoming even richer than before.