The Highly Anticipated Sequel to Holly Black’s Book of Night Is Coming — See the Cover! (Exclusive)

The sequel to Holly Black’s adult fiction debut is coming — and it’s heading for “darker places.”

Perhaps best known for co-authoring the The Spiderwick Chronicles, the bestselling fantasy author, 53, released her adult debut — and introduced readers to one Charlie Hall — in 2022 with Book of Night. Now, she is continuing Charlie’s story in Thief of Night, and PEOPLE can exclusively debut its cover.

The highly anticipated follow-up is set to hit shelves on Sept. 23, and its celestial cover teases the darkness — both literally and figuratively — to come: “Night is made of shadows… and shadows have teeth."

So does Black herself.

"With Thief of Night,” she tells PEOPLE exclusively, “I wanted to push Charlie Hall even further — into darker places, deeper magic and confronting her own shadow self. I loved exploring shadows not just as the monstrous Blights that live in this world, but as secrets, as hunger, as the parts of ourselves we pretend don’t exist until they rise up to consume everything.”

The sequel will not only be darker in nature, but will also see some drastic changes for former con artist Hall, who just can’t seem to outrun her own shadow.

"Charlie Hall, glue trap for disaster, crooked from the day she was born, who’d never met a bad decision she wasn’t willing to double down on, may have finally met her match,” an official synopsis reads.

Her love life also looks a lot different than it did when readers first met her — and her world — in 2022, Black teases. 

“After defeating Salt, and stealing her lover – the powerful shadow Vince – back from under the noses of the powerful Cabal leaders, she thought she’d won,” per the synopsis. “Agreeing to become the Hierophant and risking her life hunting down dangerous rogue shadows seemed a small price to pay if she got to do it while being tethered to Vince.”

But Vince, the synopsis says, “is no longer the man she loved. The tethering process wiped away his memories of the last year, leaving only Red — the ruthless shadow who spent years as a killer for a cruel, mercurial billionaire. Red doesn’t remember Charlie and doesn't like her.”

“So when Charlie is ordered to track down the Blight responsible for a massacre at a local church, she’s worse than just alone, heartbroken and outmatched. She’s vulnerable,” the synopsis continues. “In a world where shadows have wills of their own, the question isn’t just how to survive. It’s how to protect yourself from the one thing you can never escape — your own shadow.”

In other words, as Black teased on Instagram, readers now know Hall “was good enough to steal a shadow.” The forthcoming sequel, however, poses a vastly different dilemma — whether she has “what it takes to win back a heart.”

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Thief of Night is available for pre-order now wherever books are sold.