When the Maresh king and queen receive an enchanted necklace from White London, they send Kell to deliver a message in return.

The stone is a dangerous relic from Black London, which fell centuries ago when its people’s greed for magic exceeded their ability to control it, and all remnants of the lost world were supposedly destroyed.

Kell learns that Astrid has been controlling Rhy through the enchanted necklace, and she and Athos plan to break down the barriers between Red and White London and conquer it for their own.

Lila, feeling free for the first time in her life, decides to stay in Red London and seek out magical training.

The Guardian called A Darker Shade of Magic "a compelling, swashbuckling read reminiscent of Tim Powers’ more gung-ho fantasies".

On February 3, 2016, it was announced that Gerard Butler's production company G-BASE have acquired rights to adapt the book as a limited TV series.