The rain keeps pounding down on the camp, and the creek out in front of the boxcars begins to swell.
Rose of Sharon is feverish and sick.
Pa convinces a bunch of men to help him dig troughs to keep the creek's water from rising. They dig tirelessly.
Rose of Sharon goes into labor, and Ma and Mrs. Wainwright help her through her contractions.
The men outside continue to dig away, but a big cottonwood tree is swept up by the creek-turned-mini-raging-river, and it floats downstream. The tree gets stuck a little ways down, making the water rise even faster.
The men are freaked out by the flood, and they are also freaked out by Rose of Sharon's ear-piercing screams.
Eventually, the ear-piercing screaming stops. Pa goes inside the boxcar to check out the situation.
Mrs. Wainwright shows Pa the blue corpse of a baby.
At this point, the water has climbed up to the boxcars and cars and is inches thick.
Al tries to start the Joad truck, but the engine has been killed by the water.
Other campers become furious at Pa Joad for convincing them to stay and fight the flood with levy-building tactics. Now, no one's car will start, and everyone is stranded.
Pa and Al build a platform in the boxcar to keep the family dry. The water level is now ankle deep in the boxcar.
Ma, Pa, John, Rose of Sharon, Ruthie, and Winfield decide to find a drier and safer place.
Al decides to stay with the Wainwrights and to look out for the Joad possessions.
The Joads stumble across a barn, and they go inside to take shelter from the rain.
Inside, they find a little boy sitting next to man who is starving to death. The boy tells them that his father has not eaten anything in six days.
Ma and Rose of Sharon exchange a meaningful look, and then Rose of Sharon asks everyone to leave her alone with the man in the barn.
Rose of Sharon lies down next to the half-starved man, she puts his mouth to her breast, and she lets him drink her breast milk.
A mysterious smile comes across Rose of Sharon's face.