WARNING: The following article contains spoilers for Doctor Sleep, in theaters now.
In Stephen King's The Shining, the title referred to the supernatural abilities that can be harnessed to achieve extraordinary feats. The Torrance men could connect with ghosts roaming the Overlook Hotel, and in the sequel, Doctor Sleep, we discover this Shining is being hunted and devoured by magical vampires known as the True Knot.
They don't refer to this essence as the Shining, however; they instead call it "steam." But as the film progresses, it becomes clear that steam actually has more than one meaning.
Rose the Hat (Rebecca Ferguson) leads the Knot on their trek, which the group has undertaken for centuries, around the globe. From Europe to Asia to Africa to the Americas, they've been moving and collecting steam from victims in canisters for future use. The murder of young baseball player Bradley (Jacob Tremblay) about midway through the film provides the best insight into what steam is.
They abduct and take the boy to a field at an ethanol plant, where Rose uses a knife and slices the boy's body, bit by bit. Amid his screams, she makes it clear the pain and fear will purify the steam for them to consume. We realize it's his magical essence they're inhaling, as it leaves his mouth as breaths of steam, which they gobble up like addicts, causing their eyes to glow.
That's why they don't kill him; they torture Bradley for hours until he dies, because the steam is more potent, allowing them to live longer. The members of the Knot are close to immortal, but if they don't "feed well," they'll age and die. That leads to them tracking down Abra (Kyliegh Curran), as her steam, or Shining, is some of the most powerful they've ever encountered.
She's effectively omega-level, like Rose and key members of the Knot, and the adult Danny Torrance (Ewan McGregor). Some people, like Abra and Danny, possess steam so powerful that it can keep them off the vampires' radar. That's what resulted in the Knot feeding off the steam of weaker Shinings over the years: They couldn't find stronger steam. That feeding pattern has been a temporary and inadequate measure, though, and seeing as the Knot is made up of more than a dozen people, it isn't enough to satisfy them. That's why Rose's elder, Grandpa Flick (Carel Struycken), who's lived since the founding of Rome, withers away, and his essence is consumed by his inner-circle.
However, there's one more twist to the concept, because when Danny moves to New Hampshire and becomes an orderly at an elderly home, we see humans possess it too, except it doesn't have the magical component to it. It's just their life essence, which is why, when Danny and the cat can sense people on their last breaths, they stay to comfort them; when they die, we see their steam being exhaled. Of course, this is of no use to the Knot, because mortal steam doesn't help their quest for immortality; they want magic steam, as it also helpsto bolster their own powers while taking them a step closer to eternal life.
Written and directed by Mike Flanagan, Doctor Sleep stars Ewan McGregor, Rebecca Ferguson, Kyliegh Curran, Carl Lumbly, Alex Essoe and Zahn McClarnon.