Melody Singleton is a bright 13-year-old girl who loves math, classical music, her mom, her best friend Yaeko, and her dog. To her classmates that makes her a nerd, and they cruelly treat her as such. After being expelled from the advanced algebra class for not paying attention, she meets her new teacher, Mr. Conor, who gives her a very strange homework assignment. You see, she got kicked out because she was distracted by a symbol that the rest of us can't see, a beautiful sigil that, incredibly, Mr. Conor can see too, because it's on the assignment he gave her!

But that's just the beginning.

Her mom goes on a date to the Pier with Mr. Conor, and Melody is forced to tag along. That's bad enough. But then on the date Mr. Conor introduces her to one of his friends who freaks her out because his eyes are completely black; and then on the walk home, seagulls attack Mr. Conor and he has to be taken to the hospital!

Her weird assignment still beckons. Melody suspects that the mysterious symbol on it, and Mr. Conor's weird friend, and the seagull attack are all intimately related like the variables in an algebra equation. If she can just figure out what the sigil is, how to make it do what she wants, she knows the rest of the equation will be solved.

What she doesn't know is if she's successful, her life will be changed ... forever.