When a mysterious figure sets Emma's family altar on fire, that's one more secret to add to her list, which is growing perilously long. At the top of the list is the spectral ghosthunter named Henry, who has an attitude problem and a special loathing for Emma. Next, there's Leon, a mild-mannered ghost guardian who is as flighty as the pigeon he often turns into. There's Michelle, Emma's ride-or-die bestie, whose curiosity about ghosts often eclipses her instinct for survival. And then there's Chinese calligraphy—the magical kind. In the hands of a skilled ghosthunter, words and intention transform into magical protections. But in Emma's shaky hands, it's shiny and ineffective.

The most stunning secret, however, is that Emma's sweet, plant-loving grandmother has the power to shank ghosts! What's more, her grandma is an exorcist with a secret of her own. A secret that is haunting the Wongs from the Underworld.

The only way for Emma to save her loved ones is to tap into the Wong family's ghosthunting history. Easier said than done, of course. Hungry ghosts are one thing, but Emma's bad calligraphy may be what dooms them all!