Lucely Luna is the chief protagonist of the story. She’s 12, can see ghosts—especially those of her deceased relatives—dearly loves her father, Simon, and assists him with his public tours of haunted places in St. Augustine. Something threatens Lucely’s ghost family, making them weaker, so she recruits her best friend, Syd, and together they try to find a cure. Their early efforts accidentally unleash a curse threatening the city, but Lucely finds a magical spell to reverse the curse. She, Syd, Babette, the Purple Coven, and the fireflies combine their powers to defeat an army of attacking ghosts.

Lucely thus continues an ancient tradition by which her family works with the Coven to protect St. Augustine. In doing so, she discovers that her ability to see ghosts can help keep the peace, and she realizes she’s tougher, braver, and more able than anyone knew.

Syd Faires is Lucely’s best friend and fellow protagonist of the story. With a lifelong fascination for the occult, Syd is the perfect teammate to help protect Lucely’s ghostly firefly relatives. She’s organized and tough-minded, if sometimes impatient. Her parents are musicians, but Syd loves anything to do with magic powers, and she’s something of an expert in the subject.