

Many of the family names of the Shadowhunters used in The Mortal Instruments are first introduced in this series. She will have to learn to master them if she wants to find her brother, and must forge an alliance with Shadowhunters if she wants to survive in this dangerous world. Her search plunges her into a world she never knew existed and reveals talents she never knew she had. The first book in The Infernal Devices is entitled Clockwork Angel and begins the story of Tessa Gray, an orphan teenage girl who is looking for her brother Nathaniel Gray, who has disappeared, and seeks her true identity. As Shadowhunters consider themselves superior or purer than Downworlders or demons, they may have no qualms about killing either.

The series takes place in London England in 1878, a short time after the peace treaties between Downworlders and Shadowhunters. The books also contain many quotes referring to famous pieces of Victorian Literature like Oscar Wilde's The Importance of Being Earnest, and the works of Samuel Taylor Coleridge and Alfred Tennyson. It also features Magnus Bane, Camille Belcourt, and Woolsey Scott and other characters who appear in The Mortal Instruments series. The trilogy features William "Will" Herondale, James "Jem" Carstairs, Theresa "Tessa" Gray, and other Downworlders and Shadowhunters. The series follows Tessa's life as she lives in the London Institute with the Shadowhunters. She is forced to learn how to control this newly established power and navigate the new world she’s been thrust into. The series follows Tessa Gray, an orphaned teenage girl who discovers she has the power to shape-shift but doesn't bear a Warlock’s mark.

Cassandra Clare has stated that the two series are able to be read in any order, but it is best to read them in publication order. The trilogy is a prequel series to The Mortal Instruments series. The Infernal Devices is a trilogy by author Cassandra Clare, centring on a race called the Shadowhunters introduced in her The Mortal Instruments series.
