Twelve-year-old Alexander Cooper's life is filled with misfortunes. His family never experiences bad days, but he's about to change that. On the eve of his 12th birthday party, he discovers another boy's party has all the attention, and an online prank adds insult to injury. Desperate, Alexander makes a midnight wish for his family to have a bad day. And indeed, chaos ensues.

Alexander and the Terrible, Horrible, No Good, Very Bad Day
Alexander's day unravels after a messy morning, with gum stuck in his hair sparking a chain of mishaps.