Alice is a ten-year-old girl living in Ipswitch, Pennsylvania. She shares a deep, affectionate bond with her Aunt Polly, frequently baking beside her in the local shop. The sudden loss of her aunt leaves her feeling isolated and defensive, especially as she faces harsh criticism from her mother. She channels her grief into investigating strange occurrences around the village alongside her classmate Charlie.

Charlie is a tall, red-haired classmate of Alice who works odd jobs delivering groceries around Ipswitch. Though he does not consider himself an exceptional student, he possesses strong mechanical skills and high emotional intelligence. Having recently lost his own grandmother, he understands Alice's grief and becomes her loyal partner in investigating local mysteries.

Polly is a beloved, eccentric baker whose incredible pie-making talent brought national fame to the tiny village of Ipswitch. Winner of thirteen consecutive Blueberry Awards, she operates a local shop where she gives her pies away for free. Her sudden death creates an economic and emotional void in the community, while her unusual will sparks mass confusion.

Ruth is Alice's mother and Polly's younger sister. She harbors deep-seated jealousy toward Polly, feeling completely overshadowed by her sister's popularity and baking talent. Following Polly's death, Ruth decides to start baking pies herself, determined to win the Blueberry Award and prove her own worth.

A visitor to Ipswitch who presents herself as a magazine reporter writing an article about Polly's legacy. She displays an intense interest in locating Polly's secret piecrust recipe. Her inquiries and presence in the village coincide with a series of strange occurrences surrounding Polly's former shop and belongings.

George is Alice's father and a former vacuum salesman who now runs a souvenir shop next to Polly's bakery. He generally avoids household conflict, preferring to read the newspaper rather than engage in arguments. When tensions rise between his wife and daughter, he consistently instructs Alice to defer to her mother.

Lardo is a highly disagreeable, overweight white cat originally adopted by Polly. Named after a brand of vegetable shortening that matches his coat, he hisses and claws at nearly everyone. Polly's will dictates that the cat goes to Alice, and mysteriously names "Lardo" as the inheritor of her famous piecrust recipe.

Miss Gurke is the strict principal of the local school attended by Alice and Charlie. She is known for her disciplined environment and her habit of wearing oversized clothing. Her unusual behavior following Polly's death makes her an early subject of Alice's investigative curiosity.

Nora is the daughter of the local mayor and a classmate of Alice and Charlie. She maintains a slightly haughty demeanor, keeping her distance from Alice while occasionally interacting with Charlie.

The mayor of the small village of Ipswitch. He holds the official leadership title in the community but often relies heavily on the political drive of his wife to maintain his standing.

Melanie is the ambitious wife of Mayor Needleman. She possesses strong political instincts and quietly channels her drive through her husband's position in the village.

Chief Decker is the head of the local police force in Ipswitch. He investigates the break-in at the pie shop but frequently dismisses Alice's theories, preferring to attribute the town's recent crimes to mischievous teenagers.

The local minister in Ipswitch who presides over Polly's widely attended funeral. He is surprised to discover that Polly bequeathed her valuable pie shop to him to help raise funds for the church.

Mr. Ogden is Polly's estate attorney. He bears the responsibility of executing Polly's highly unconventional will, summoning Alice to his office to deliver both the confusing document and a highly uncooperative cat.