At the end of Chapter 27, Lee gives the reader an indication that something significant is about to happen. The chapter ends with Jem agreeing to take Scout to the pageant. Scout narrates, "Thus began our longest journey together."
In Chapter 28, as they make their way to the pageant, Jem teases Scout about "haints" (ghosts) as they walk past the Radley house. Jem is teasing because they are on their way to a Halloween pageant, but this adds to the suspense. Scout trips on a root so they are looking at the ground as they go. Looking at the ground and feeling their way through the dark, they are completely surprised by Cecil Jacobs when he jumps out to scare them. This is what foreshadows the moment when Bob Ewell attacks them on the way home from the pageant.
As they make their way home, Jem and Scout hear suspicious noises and they suppose that it is Cecil. When Cecil fails to jump out, they begin to think it is not him following them. Jem asks Scout to take off her costume so they can pick up the pace. She can't do so in the dark and she notices that Jem is starting to worry:
Jem was talking in an unhurried, flat toneless voice. I wondered how long he would try to keep the Cecil myth going.
At the beginning of Chapter 28, Harper Lee foreshadows Bob Ewell's attack by creating an ominous atmosphere during the night of the Halloween pageant. Lee writes that the night was unusually warm and there was no moon in the sky. In literature, conflict is sometimes associated with warm or hot weather, which is a time when passions usually run high. Also, the darkness of the night is a significant element that adds to the foreboding atmosphere. Lee again foreshadows Bob Ewell's attack by writing, "High above us in the darkness a solitary mocker poured out his repertoire in blissful unawareness of whose tree he sat in, plunging from the shrill kee, kee of the sunflower bird to the irascible qua-ack of a bluejay, to the sad lament of Poor Will, Poor Will, Poor Will" (157). Throughout the novel, mockingbirds symbolize innocent beings, while bluejays represent malevolent beings like Bob Ewell. The mockingbird that sings at the beginning of Chapter 28 symbolizes Boo Radley and the Finch children, while the bluejay symbolizes Bob Ewell. Lee again foreshadows the attack by writing, "We turned the corner and I tripped on a root growing in the road. Jem tried to help me, but all I did was drop my costume in the dust" (157). The fact that Jem tries to aid his sister but cannot is significant. During Bob's attack, Jem tries his best to help his sister, who cannot defend herself because of her cumbersome costume.