Mia Winchell appears to be a typical kid, but she's keeping a big secret—sounds, numbers, and words have color for her. No one knows, and Mia wants to keep it that way. But when trouble at school finally forces Mia to reveal her secret, she must learn to accept herself and embrace her ability, called synesthesia, a mingling of the senses.

Her younger brother Zack keeps a chart of all the McDonald's hamburgers he's eaten in his lifetime. Her older sister Beth dyes her hair a different color every week and might be a witch. When trouble in the school finally convinces Mia to reveal her secret, she feels like a freak; and as she embarks on an intense journey of self-discovery, her family and friends have trouble relating to her. By the time she realizes she has isolated herself from all the people who care about her, it is almost too late. Mia has to lose something very special in order to understand and appreciate her special gift in this coming-of-age novel.