In A Darker Shade of Magic, V.E. Schwab introduces readers to a world where parallel Londons exist—each one with varying degrees of magic. The story follows Kell, a magician who can travel between these worlds. He is one of the last Travelers—rare magicians who can move between these different Londons. The four Londons are: Red London, where magic is alive and well. Gray London, which is devoid of magic. White London, where magic is dying, and people fight to control it. Black London, a forbidden world where magic consumed everything, and now it is nothing but a dangerous memory. Kell, who serves as an ambassador for Red London, is caught in a dangerous situation when he smuggles a dangerous artifact from Black London. He meets Delilah (Lila) Bard, a pickpocket from Gray London, who forces him to take her on a dangerous journey between the worlds. Together, they uncover a conspiracy that threatens not only their world but all the parallel Londons.