Dangerous Habits is a six-issue Hellblazer story arc written by Garth Ennis with art by Will Simpson published by DC Comics' Vertigo imprint. Dangerous Habits collects issues #41-46 of the Hellblazer series. The story features the occult detective John Constantine, who at that time caught terminal lung cancer, and subsequently conning the Lords of Hell to cure it, mixing contemporary horror with Faustian theme. The comic became a success, being well-received and was the best-selling Vertigo series of that time. It also catapulted Ennis' career in the American comic book industry.