The book opens with Greg Heffley saying how bad his life is, with middle school, and his dysfunctional family, and his best friend Rowley Jefferson, whom Greg worries about, and the moldy cheese out of the blacktop, telling once, a kid named Darren Walsh touched it, and it started a link called the "Cheese Touch."
Greg faces many hardships, including Halloween. As Greg and Rowley, go Trick-or-Treating, teenagers chase them and they barely escape when they get to Greg's grandma's house and make monkey noises at them its all good until they get home and Greg's dad throws water at them and water soaks their candyGreg and Rowley's friendship is starting to fall apart. Greg invents a game where one person would throw a football to make the other fall off the Big Wheel, A gift Rowley got for Christmas, however when Rowley falls off ,he breaks his arm. Greg is jealous of the attention Rowley is getting. Rowley is also framed for scaring kindergardeners, when it was Greg wearing Rowley's coat. When Greg confesses, Greg is kicked out, and Rowley is promoted. Rowley also declares himself the owner of a comic strip, Zoo-Wee-Mama, that was created by Greg and Rowley, but Greg drops out to make his own comic strip. The two stop being friends.
Greg and Rowley get into a fight at the blacktop, when the teenagers from Halloween come, and grab Greg and Rowley. They make Rowley eat the cheese, and are to make Greg do it too, but Greg finds a way out. When they go away, when people notice the cheese is gone Greg lies and says he threw it away this gives Greg the Cheese Touch. Greg and Rowley becomes friends again, and Greg even says the good advantages of having the Cheese Touch.