Kelly, Hannah and Darbie are on the hunt for a special ingredient in order to determine Chuck's whereabouts. The ingredient only blooms once a year - on Halloween. The Girls have to find a way to go back to last year's Halloween and get it without running into their past selves.
Using the special ingredient the girls gathered from last Halloween, they cook up a Miso Soup to determine Chuck's location. However, when that fails to work, Kelly instead cooks a "Settle the Beef" sandwich in order to draw Chuck to them instead...but in order for it to work, Kelly has to spell her own Grandma.
The girls have their first interaction with Chuck, but it quickly becomes clear that he is suffering from some sort of amnesia. He doesn't remember anything about the Pluot Festival in 1965. Grandma and Mama P think he's lying and can't be trusted, so the girls cook a trust spell that helps Chuck adjust to the modern day - but it also unlocks some of his memories from 1965.
Unable to get consistent answers from Grandma, Ms. Silvers, or Mama P about exactly what happened with Chuck in 1965, Kelly, Hannah and Darbie cook a recipe that allows them to observe past events. Meanwhile, Chuck gets closer to the Quinn family when he saves Buddy from a skateboarding accident.
Worried that Chuck is getting too close to her family, Kelly and Darbie cook a special mint that acts as a lie detector, so that she can get her Dad to see through Chuck's act. Darbie uses the mint on her own Dad when he invites her to lunch to meet his new girlfriend Amy.
When the girls cook a fix it spell to help repair Jake's food bike, they find themselves compelled to remedy all problems, from repairing cabinets to helping Mama P spruce up the café. In the end, Kelly crosses paths with Chuck realizing he needs some emotional fixing.
The book leads Kelly to Chuck's hideout, hidden by an invisibility spell he cast. Kelly makes herself invisible in order to get inside, and is shocked to discover that Chuck is making his own magic cookbook.
Kelly cooks a secrets spell searching for answers to the Chuck mystery. The spell reveals more questions than answers when everyone around her is compelled to tell her their secrets, culminating in the biggest secret of all - one that is hidden within the pages of the book itself.
Kelly, Hannah and Darbie are racing to solve the final mystery within the pages of the book before Chuck manages to trap one of them inside the book for all time. Along the way, they learn a surprising bit of information about Chuck's past and his family.
Kelly, Hannah and Darbie try a spell on Mama P to help her remember magic but it backfires and they take away Mama P's personality, which then passes from person to person as the whole town starts to act like Mama P.
Hannah discovers new evidence that leads the others to believe that Mr. Morris, her tough new teacher at Fox Canyon, is the suspect who is cursing people. They cook a spell to protect anyone from entering Kelly's spell, but the moment the magical barrier goes up, Mr. Morris is already inside. There to work on Terri's mayoral campaign with Kelly's mom and her political advisor Jill. They are stuck together until they can find a way to cook a counter-spell without anyone noticing.