Lucifer, the long-time Big Bad of Supernatural, is a biblical villain that literature and pop culture at large has been obsessing over endlessly since his inception. Depending on the story he appears in, the fallen angel invariably acts as the physical manifestation of pure evil, tempting his God's flawed creations into sinful ruin, or -- for the more satanically-sympathetic -- an eternal symbol of rebellion who was damned for railing against the status quo.

Physical depictions of the ruler of Hell similarly vary from the red-skinned, cloven-hooved and horned type, as seen in everything from Legend, to South Park to Good Omens; to a less fantastical human shell, a form that allows him to walk among us in order to personally sow discontent throughout Earth, as played by Al Pacino in The Devil's Advocate; Peter Stormare in Constantine, Elizabeth Hurley in Bedazzled and, most recently, Tom Ellis in Lucifer, to name just a few.

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Supernatural's own Lucifer, played predominantly by Mark Pellegrino, takes a cue from the latter characterization and visual cues: crafting a human-suited, sandy-haired Satan whose deadpan wit can barely mask the broiling malice that has been poisoning his angelic heritage for centuries. With an overcrowded back catalogue of past performances in other media to contend with, it's impressive that The CW series not only managed to come up with an iteration of the Devil that was at all fresh and interesting, but has also -- for the most part -- remained interesting over 14 seasons.

SYMPATHY FOR THE DEVIL

Supernatural Lucifer

Our relationship with villains has changed dramatically in recent decades. No longer are we content to accept the black-and-white morality of fairy tales -- we want to get right under the skin of monsters and find out what makes their black hearts tick. Contributing to this trend, in Supernatural, nothing is cut-and-dry, including the Devil himself.

Even before Lucifer showed up, Sam and Dean wrestled with determining whether or not the monsters they'd been trained to kill were beyond being able to live bloodless existences, while an early antagonist was a human hunter unable to do just that. The arrival of the angel, Castiel, in the Season 4 premiere, appeared to confirm for the first time that there was holy light among the nebulous, unholy dark... only to instead reaffirm that no living thing is entirely good nor bad. Or, as creator Eric Kripke put it: "Angels! But they're dicks."

This humanization extends, naturally, to the biggest "dick" of them all -- former Archangel, Lucifer. Rather than a pantomime figure of evil, Supernatural's Lucifer is portrayed, under all the murderous psychosis, as a son who feels betrayed and abandoned by his dad, with his apocalyptic shenanigans more cosmic cries for attention than hollow acts of destruction. What's a higher being to do when your only parent kicks you to the curb in favor of his new kids? Act out, of course. This dynamic, of course, parallels Sam and Dean's tumultuous relationship with their own flawed and perennially absent father, further connecting us to the more human elements of humanity's would-be destroyer.

With almost meta-awareness, Lucifer has pulled at this connective tissue between his angelic siblings and the Winchesters before, once opening up to Sam that he too was made to feel like a "freak" by his older brother Michael, who he "loved" and "idolized." Not only are angels dicks, but they have family dramas just like us.

SAME SATAN, DIFFERENT FACE

Lucifer Sam Winchester Supernatural

Mark Pellegrino gives the Devil his signature, dead-eyed smirk throughout most of Supernatural, but, as part of its effort to stave off the threat of stale storylines over the course of its extra-long shelf life, the series has given evil a few different faces here and there.

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Sam Winchester, the descendant of Cain and, appropriately, the more rebellious of the Winchester brothers, is Lucifer's "true" vessel, making every other "meat suit" a temporary stop-gap. All he needs to do to gain entry to said stop-gaps is a "yes," which immediately implicates the consenting person in clearing the path to their own damnation. While not inhabiting a vessel, Lucifer is left to exist in perhaps his creepiest form: a disembodied voice whispering sweet, satanic nothings into his victims' ears.

As well as Sam, Lucifer has used nuns and bishops as mouthpieces -- his own twisted irony, of course -- taken up residence inside an aging rockstar, and even slipped inside Castiel. His most impressive get? The President of the United States, which leads to two ludicrous but fun storylines: the Winchester brothers being arrested for attempting to assassinate the President, and the birth of the antichrist, a Nephilim later named Jack and taken under the Winchesters' fatherly wings.

WHO IS THE MONSTER, WHO IS THE MAN?

Lucifer Superntural

What is the Devil to do when there are no idle hands left to make work for? Following -- Idris Elba in Pacific Rim-style -- the cancelation of his long-planned Apocalypse in Season 5, Supernatural put Lucifer on the backburner as it shifted into an alternating roster of major antagonists for Sam and Dean to fight in each new season.

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Once he broke out of Hell -- again -- Lucifer, aside from a few civil wars with Crowley, the self-appointed King of Hell, and a custody battle with Sam, Dean and Castiel over Jack, slid into a more familial position as a constant but less significant thorn in Team Free Will's side.

That was until he appeared to be permanently vanquished to The Empty -- the afterlife for angels and demons -- in Season 13. Finally free, Nick, Lucifer's main vessel, was given a chance to reclaim his life, which he began in earnest by trying to solve the mystery of what happened to his murdered wife and son around the time of his initial possession. Gradually though, Nick's journey became an increasingly brutal one, leading us to wonder, during his years of doing unspeakable things under the Devil's influence, where Nick ended and Lucifer began. With a long trail of bodies behind him, Nick desperately preyed -- not to God, but to the Devil, begging his kindred spirit to return to him.

This late revelation about Nick/Lucifer's symbiotic bond added an unexpectedly fascinating undertone to a character we rarely get to spend this much time with in other media, underlining in chilling fashion that Lucifer may have been right all along to not bow down to his father's preferred, imperfect children all those centuries ago.

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