In the deepest recesses of the ocean, Graciela--once an ordinary girl--now makes sea glass and assists her friend, Amina, as she welcomes newly awakened sea ghosts from their death sleep. Though Graciela's spirit is young, she has lived at the bottom of the ocean for more than a hundred years. Meanwhile, in the mortal world on land, twelve-year-old Jorge Leon works in his family's forge. He's heard of the supernatural spirits living beneath the ocean's waves--tales that do nothing to quell his fear of the water. But when Jorge discovers a hand-wrought harpoon with the power to spear a sea ghost, he knows he must destroy it any way he can.

When the harpoon is accidentally reunited with its vengeful creator, unlikely allies Graciela and Jorge have no choice but to work together to keep evil spirits from wreaking havoc on both the living and the dead. If only the answer to saving what they care about didn't lie within the depths of the abyss . . . Newbery Medal winner Meg Medina and illustrators Anna and Elena Balbusso have crafted a thoughtful tale infused with magic and high-stakes adventure that will leave readers wondering what power lies in the depths of the ocean--and inside each of us.