Doctor Sleep serves as a sequel to the events of The Shining movie, not the book, but it does give Stephen King's version of Room 237 a shout out. As has long been well-known, King is far from a fan of Stanley Kubrick's adaptation of The Shining, even though most now consider it one of the greatest horror films of all time. As the writer of the source material, and a pop culture giant in his own right, King is certainly entitled to his opinions about the movie, and some - like Jack Torrance appearing crazy from the start instead of slowly descending into madness - are hard to argue with.

Whether or not The Shining is a good adaptation of King's novel or not, few would disagree with it being called a great film. Kubrick's Shining targets its audience like few horror movies ever have, seeking to keep viewers unnerved, scared, and entirely off balance for nearly the film's entire 2-hour-plus running time. In that sense, Doctor Sleep is a worthy successor, as most reviews suggest it at least attempts to do the same.

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One of The Shining's most iconic moments involves the infamous ghost in Room 237, a woman who died by suicide in the room's bathtub, and now awaits anyone who dares enter. However, a minor detail was changed about the room from book to film, and Doctor Sleep throws in a sly wink to the original version.

Stephen King's constant readers will remember that in The Shining book - and the 1997 TV miniseries adaptation that King penned himself - the Overlook's water-logged ghost actually inhabited Room 217. However, this was changed for Kubrick's film at the request of The Timberline Lodge in Oregon, which was used for exterior shots of the Overlook Hotel. That resort actually had a Room 217, and was afraid the movie would lead to their room not being stayed in, so Room 237 was used, since Timberline has no Room 237. Amusingly, the movie had the opposite effect, with a surge in interest for Room 217, likely spurred on by those familiar with both the movie and book.

While Doctor Sleep does indeed adapt the major story elements of King's book of the same name, some changes were made necessary when the decision came to have the film be a sequel to Kubrick's Shining. Since Dick Hallorann died in the movie, he's dead in this take on Doctor Sleep. Since the Overlook Hotel wasn't destroyed in Kubrick's film, it still stands in Doctor Sleep. This is also true of Room 237, which is still called as such in Doctor Sleep. However, in a clever subtle nod to King's book, the room number of the first dying patient that Danny Torrance comforts as they go - earning him the titular moniker - is 217. It's a small but delightful Easter egg for King fans, and a sign of the respect Doctor Sleep director Mike Flanagan has for the source material.

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