Set in the American South, the action in the novella begins on the last Friday in August 1944. On Sunday, Frankie Addams's brother Jarvis is getting married to Janice Evans. This fact unnerves the pubescent Frankie. She hangs around the house feeling trapped, isolated and scared. Frankie is twelve years old, and is in the middle of a growth spurt and is stuck somewhere between the childhood of her six-year-old cousin John Henry West and the older teenagers who will not play with her.

On Friday evening, Frankie plays cards with John Henry and with her African- American housekeeper, Berenice Sadie Brown. Frankie ruminates over the upcoming wedding. She has trouble fathoming what it means to get married. Berenice insightfully states that Frankie is simply jealous.

Frankie invites John Henry to sleep over, claiming that he seems frightened. The two undress with their backs to each other and climb into bed together. Frankie has wanted to sleep in the same bed with someone all summer. As we later learn, she used to sleep next to her father, but he evicted her at the beginning of the summer, saying she was too old.

The following morning, Saturday, John Henry, Berenice and Frankie sit on the front porch and talk about Christmas. Then, very subtlely, McCullers skips over the entire day and begins describing a card game between the three of them that takes place at 5:45 PM. At one point, John Henry refuses to play a jack of spades next to the queen of spades and Frankie becomes angry that he doesn't know the rules. Later, Frankie gives John Henry one of her dolls to keep, as if passing on her youth.

McCullers writes that "This was the summer when for a long time she had not been a member." Meaning that she was excluded from all other groups of humans. Frankie dreams of running away from her surroundings in hopes of a better life. She remembers the House of the Freaks at the local fair and begins to wonder if she will become one of them, should she continue to grow so rapidly. At the end of Part One, Frankie realizes that Jarvis and Janice are the only two people with whom she is a part of a collected group. She thinks of changing her name to F. Jasmine, so as to also have a name beginning with J A.

Frankie does not appear to know about sex, yet she fears it. During the summer, in addition to stealing from Sears and shooting her father's gun in a vacant lot, she "committed a queer sin" with her friend Barney MacKean in his garage. Whatever it is she did causes her great remorse and hatred toward Barney. We also learn of a time when she witnessed a couple, Mr. and Mrs. Marlowe, who were boarding in her house, doing what we can safely assume was having sex. However, a horrified Frankie thought Mrs. Marlowe was "having a fit." Further, her tomcat recently ran away and Frankie was surprised and confused when Berenice said he went to look for a female.