Locke & Key: Clockworks #4
Clockworks, chapter 4: "The Whispering Iron." The tamers of The Tempest -- Rendell Locke, Dodge Caravaggio, and their friends -- descend into the Drowning Cave to open the Black Door, hoping to get their hands on some of the fabled whispering iron, the material from which all of the keys are forged. And everything goes according to plan! Not.