Not all of The Sandman’s characters were dreamed up by Neil Gaiman.
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Netflix’s The Sandman adapts the Vertigo comic series of the same name. Many of its characters are drawn from fiction and mythology, but plenty also have a surprising history in DC comics.
Dream’s appearance and demeanor haven’t changed much from the comics. He changes form frequently, which we see a bit of in the show, but it’s more extreme in the comics (at one point, for example, he shows up as a cat).
Like Dream, Death takes many forms in The Sandman comics, but we usually see her as a cheery woman wearing an ankh. Outside of The Sandman and her own spinoff miniseries, she’s turned up in The Flash, Lucifer, and other DC titles.
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Matthew mentions being a former human in The Sandman. That human happens to be Matt Cable, a Swamp Thing character who fell into a coma after a car accident and eventually died. His comatose state put him in the Dreaming, so he was able to join the realm instead of going with Death.
Lucifer needs no introduction. The Lord of Hell and a fallen angel, he’s a cruel deceiver in both religious tradition and popular consciousness. In The Sandman, stories, myths, and beliefs blend as Lucifer rules over a Hell as real as Earth.
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Lucifer has also taken on a life of his own in DC comics. Outside of his multiple storylines in The Sandman, he has his own comic series, which got a TV adaptation before Dream came to Netflix.
That name may ring a bell to DC fans. John Dee is Doctor Destiny, a Justice League villain who manipulates reality with a gem called the Materioptikon.
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In the comic, it’s John Constantine who meets Morpheus. The demon hunter’s plotline remains the same, and he’s just as hard to get along with as Johanna.
Hector (Lloyd Everitt) and Lyta (Razane Jammal) don’t change much from comics to show. After Hector’s death he visits Lyta in a dream, where they conceive a child. Dream ends the season by declaring the child is “his,” though what that means won’t become clear until much later.