Henry James’ classic ghost story is one you’ll find reading over and over again, only to say, “Wait…what?” After the death of their parents’, a young boy and girl are put in the care of their Uncle Douglas. He hires a governess to care for him in his country home, where she begins seeing ghost-like figures roaming about the grounds. It only gets stranger from there, and the ending will leave you wondering if any of it was real.

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Shutter Island bends ‘reality,’ and leaves the reader wondering what actually happened. U.S. Marshal Teddy Daniels and his partner head to Shutter Island, home to Aschecliffe Hospital for the criminally insane, to investigate the disappearance of a patient. It only gets creepier from there, as Teddy explores the desolate island and uncovers secrets of his own.

Cadence Sinclair spends her summers on her grandparents’ private island near Martha’s Vineyard. During Summer Fifteen (her fifteenth year on the island) she falls in love with a boy named Gat, but tragedy strikes when there’s an accident that causes her to lose her memory of that summer. As Cadence finally returns to the island two years later, she puts together the horrifying pieces of what happened that night—with a twist that’ll leave you broken.

When Nora is invited to the bachelorette party of an old college friend she hasn’t spoken to in years, she’s surprised but attends anyways. But when she wakes up in the hospital with no memory of the events that put her there, things become even more suspicious. An unreliable, amnesiac narrator tells this story, which has a deadly twist you won’t believe.

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The twist ending in the third Hercule Poirot detective novel revolutionized the genre forever. After a retired Poirot’s friend is murdered, he is determined to uncover the truth behind the killing. Master mystery writer Agatha Christie leads us through a windy road, full of lies and deceit to deliver us a startling and unsettling conclusion.

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Originally published in Argentina as La pregunta de sus ojos, the novel follows Benjamín Chapparro—a retired detective obsessed with the cold case of a young woman who was murdered and raped in her own bedroom. He revisits the case, determined to catch the monster that committed this crime. The shocking twist ending will have you feeling satisfied and confused all at the same time.

Some people love it, some people hate it, but regardless: This book has one crazy twist at the end. Sisters Dara and Nick were best friends, until an accident left Dara’s face scarred and their relationship shattered. When Dara vanishes on her birthday, Nick is convinced the disappearance is linked to another missing girl and is determined to find her before it’s too late.

Paula Hawkins’ popular thriller, which was just adapted into a movie, follows unreliable narrator Rachel and a series of events that follow her after a woman whom she watches from her commuter train window each morning goes missing. If you think that sounds weird, it only gets stranger. Hawkins’ ending will keep furiously flipping through the pages towards the shocking conclusion.

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