Greg Heffley z nestrpnostjo pričakuje začetek novega šolskega leta, saj bo od zdaj naprej hodil že v sedmi razred. Medtem se njegova starša trudita svojega mlajšega sina čim bolj zbližati z njunim starejšim sinom Robijem, a kaj, ko ne vesta, da je Greg vedno žrtev nagajivosti in potegavščin svojega brata. Tudi tokrat ni nič drugače, saj Robi izkoristi vsako priložnost, da za hrbtom svojih staršev muči nemočnega Grega.
Greg and Rodrick don't get along, and his parents are fully aware of that. In order to help them get along, Greg's mother introduces Mom Bucks, which rewards them for getting along. But Rodrick isn't the only problem. He has to deal with any conflicts involving Holly Hills, as well as other embarrassing situations. Will Greg and Rodrick get along?