Sixteen-year-old Clary continues trying to make sense of the swiftly changing events and relationships in her life as she becomes further involved with the Shadowhunters and their pursuit of demons and discovers some terrifying truths about her parents, her brother Jace, and her boyfriend Simon.

While working at pleasant but mundane summer jobs in San Francisco, fifteen-year-old twins, Sophie and Josh, suddenly find themselves caught up in the deadly, centuries-old struggle between rival alchemists, Nicholas Flamel and John Dee, over the possession of an ancient and powerful book holding the secret formulas for alchemy and everlasting life.

"Lockwood & Co. are hired to investigate Edmund Bickerstaff, a Victorian doctor who reportedly tried to communicate with the dead, while Lucy is distracted by urgent whispers coming from the skull in a ghost jar"--

When a madman is on the loose and Miss Peregrine in peril, Peculiar Children Jacob Portman and Emma Bloom stage rescue missions, meet new allies, and face great dangers.

Sixteen-year-old Tessa Gray travels to England in search of her brother only to be abducted by the Dark Sisters, residents of London's Downworld, home to the city's supernatural folk, and she becomes the object of much attention--both good and bad--when it is discovered she has the power to transform at will into another person.

Known and feared as the White Wolf, Adelina Amouteru and her sister flee Kenettra to find other Young Elites in the hopes of building her own army of allies. But as Adelina's powers (fed only by fear and hate) start to grow beyond her control, she also distrusts her newfound Elite friends. Teren Santoro, leader of the Inquisition, wants her dead. And her former friends, Raffaele and the Dagger Society, want to stop her thirst for vengeance. Adelina...

Still pursuing a cure for her mother's enchantment, Clary uses all her powers and ingenuity to get into Idris, the forbidden country of the secretive Shadowhunters, and to its capital, the City of Glass, where with the help of a newfound friend, Sebastian, she uncovers important truths about her family's past that will not only help save her mother but all those that she holds most dear.

Nicholas Flamel and teenaged twins Josh and Sophie Newman return to San Francisco where a weakened Flamel reunites with his wife, Perenelle, hoping to use his remaining power to prevent the monsters on Alcatraz Island from escaping. Meanwhile, Dr. John Dee and Machiavelli continue to seek power and the twins desperately try to determine who they can trust as they search for Scatty and an immortal who can teach Josh the magic of fire.

Josh has chosen to side neither with his twin sister Sophie nor Nicholas Flamel, but rather to fight alongside Dr. John Dee and Virginia Dare, while the immortal Machiavelli and Billy the Kid plan to set loose the monsters of Alcatraz on San Francisco.

"With the help of some unexpected and rather ghostly allies, Lockwood & Co. must battle their greatest enemy yet, as they move ever closer to the moment when the earth-shattering secret of 'the problem' will finally be revealed"--