Greg Heffley has always been in a hurry to grow up. Being older means you can live alone, eat whatever you want for dinner and don't have to share with your brothers. PERFECT.
At least, that's what Greg thought, but it turns out there's a lot more to growing up like dealing with boy/girl dances, increased responsibilities and awkward changes.
一心渴望快快長大並且變man的葛瑞，逐漸發現成長路上似乎不如預期的美好……期待已久的健康教育課充斥著過時落伍的資訊，他還很有可能因為一顆蛋而慘遭當掉的厄運；老爸希望他更有責任感一點，偏偏葛瑞連用鬧鐘叫醒自己都辦不到。終於，家族裡的大家長曾祖母看不下去，把葛瑞叫來「談心」，沒想到，人生經驗豐富的曾祖母非但沒有指引明路，反而把葛瑞嚇得落荒而逃？！
囧葛瑞不僅要面對青春期的劇烈變化，好搭檔榮利又遲遲不肯跟他和好……這一回，註定要單打獨鬥的葛瑞究竟能不能平安順利的轉大人？
——中文簡介摘自未來出版出版《葛瑞的囧日記5：青春期了沒?》