John Constantine, Hellblazer: All His Engines is an original graphic novel featuring the DC Comics character John Constantine, written by Mike Carey, with art by Leonardo Manco. The graphic novel is a spin-off of the long-running series Hellblazer, published by the DC Comics imprint Vertigo. It was first published in January 2005. The graphic novel follows John Constantine's investigation into a worldwide phenomenon that is placing innocent people into comas. The graphic novel was adapted into the animated series (later compiled as a direct-to-DVD film) titled Constantine: City of Demons.