Maycomb gets a season it hadn't seen in a while: winter.
Mr. Avery tells the kids that bad children makes the seasons change, which—what?
Mrs. Radley dies, and Atticus goes to pay his condolences at the Radleys. When he comes back Jem and Scout pounce on him to ask if he saw Boo in the flesh (he didn't).
Scout is terrified when she wakes up one morning to see white stuff pouring from the sky.
Yep, it's snow.
School is cancelled, so Jem and Scout set out to make a snowman, though they don't really know how and there isn't much snow.
That night, it's freezing.
Atticus wakes Scout in the middle of the night because Miss Maudie's house—next door to the Finches'—is on fire.
Once the fire is finally put out (and Miss Maudie's house reduced to a smoking hole in the ground), the Finches return to their fortunately undamaged home.
And then Atticus notices something. Scout is wrapped in a blanket that she didn't have when she left the house.
Scout says that she stayed right where he told her to, in front of the Radley Place, but she and Jem saw Mr. Nathan fighting the fire. So if he wasn't the stealthy blanket-deliverer, it must have been some other occupant of that house.
Hmm, who could that be?
Jem tells Atticus all about the knothole and the cement and his mended pants.
Atticus finally says outright that it must have been Boo Radley who brought the blanket, and Scout, who's been late for the clue train, is hit by belated terror.