Part II begins six months after Nastassya Filippovna's party. Two days after that November evening, Prince Myshkin left St. Petersburg for Moscow. According to some rumors, he claimed his inheritance, which turned out to be smaller than initially expected. Furthermore, the inheritance shrank considerably because a large number of creditors suddenly appeared, and the prince satisfied all their claims.

Nastassya Filippovna and Rogozhin left that night for Yekaterinhof, but after a weeklong orgy there with Rogozhin and his company, Nastassya Filippovna ran away to Moscow. Rogozhin soon left for Moscow as well. Ganya fell ill after the party; when he was given the package with the money that Nastassya Filippovna left for him, he asked Myshkin to return the money to her. When the prince left, he and Ganya parted as friends.

The Yepanchins heard news of Myshkin through rumors and letters of the old Princess Belokonskaya, who wrote to Madame Yepanchin. The prince had obviously left quite an impression on the Yepanchin household, but General Yepanchin's wife refused to mention Myshkin's name before Belokonskaya's letters gave reason to once again speak of him. The Yepanchins also learned that Rogozhin found Nastassya Filippovna in Moscow. She ran off again, but came back and promised to marry him. Then she suddenly ran off for a third time, just before the wedding.

The Yepanchins made plans to spend the summer abroad; Alexandra's engagement to Totsky never finalized. However, the plans for a trip abroad were thwarted by the appearance of a certain Prince S., who became interested in Adelaida. The wedding was set for next spring. Meanwhile, a dashing twenty-eight-year-old named Yevgeny Pavlovich Radomsky began to show interest in Aglaya, which further postponed the trip abroad.

As for the Ivolgins, a lot changed in their household in these six months. Varya married Ptitsyn. Nina Alexandrovna and Ganya moved to Ptitsyn's house with Varya. General Ivolgin was put in debtor's prison, largely due to the efforts of his mistress, the widow of Captain Terentyev. Nina Alexandrovna secretly visited him in prison. Kolya became friends with the Yepanchins, and the only member of that family who did not like him was Aglaya. One day Kolya brought Aglaya a letter from Myshkin in which the prince merely asked her how she was doing and said he wished for her happiness. The Yepanchins left for their summer residence in Pavlovsk, a small town near St. Petersburg.

After his six-month absence, Myshkin comes into the train station in St. Petersburg. He feels a pair of eyes watching him, but he cannot recognize their owner. After checking in at a hotel, the prince goes to the house of Lebedev to try to find out Nastassya Filippovna's whereabouts. Lebedev and his children are in mourning because Lebedev's wife has recently died in childbirth. Myshkin meets Lebedev's nephew, whom he does not like for some reason. Lebedev chatters on about his reading and praying, such as his prayers for Madame du Barry, a mistress of Louis XV who has been guillotined. Lebedev's nephew tells the prince that Lebedev frequently tells lies, simply from habit.