Penny Dreadful has spent its second season gleefully dismantling audience expectations amid high-gothic imagery and subtext. One of its major arcs this season is a deconstruction of the Bride Of Frankenstein, as the good Doctor kills and resurrects prostitute Brona to sate the demands of his first creation, Caliban. But in the season’s eighth episode, Brona (now renamed Lily) turns the tables on Caliban—a student of poetry and mythology with some distasteful ideas about what Lily owes him—by propositioning him first. The deal: She’ll be his lover if they kill their maker together. And the term of endearment that seals the deal for mythology-buff Caliban? She wraps her arms around him and calls him, “My brother.”
It’s a small but telling moment, meant to add a further frisson of the illicit and a suggestion of the doomed without actually stopping the proceedings. But there’s also a sad truth to the words; they’re unique in the world, and have only each other to rely on for true understanding. They’re apart from others, and fated to want the same thing. And in deconstructing this trope, Penny Dreadful hits on why sibling incest is such a popular—and tricky—TV fallback.
Consensual sibling incest as a fulcrum for narrative is nothing new; it’s been a powerful storytelling dynamic since people started telling stories. It’s a taboo that suggests some inherent separation from the accepted, but avoids the power imbalance (and even deeper taboo) of incest between generations, which is almost always depicted in myth as a curse rather than as merely outré. Brother-sister relationships appear in Egyptian, Norse, and Greek legends, often between heroic deities, and in many of those tales the offspring from those pairings are destined for something equally mythic. Later stories walk an uneasy line between mythic incest and real-life taboo; Arthurian myths heavily feature Morgana and Arthur’s tragic and unwitting union, and emphasizes the bittersweet destiny of their son Mordred, who eventually slays his father.
And despite providing endless fodder for parody—Supernatural has broken the fourth wall repeatedly to make fun of incest ’shippers, and The Spoils Of Babylon riffed on sweepingly earnest star-crossed sibling lovers for hours—it’s a taboo that still entices. Its inherent sense of danger and implication of overwhelming passion makes it an evergreen source of forbidden interest. It’s a family battle without the violence, a Greek tragedy without the need for gods, and an insta-obstacle for its lovers to struggle against. But there’s just enough pathos beneath the suspense that even when the context isn’t mythic, the sense of inevitability still is. It’s a nearly foolproof narrative combination that’s thousands of years old, and has only become more popular as serial storytelling takes full advantage of the narrative tension it provides. Victorian potboilers couldn’t get enough of the “I feel a strong pull to this amnesiac about the same age as my long-lost sister” trope, and neither can we.
In modern television, parent/child incest is still the skin-crawling territory of Law And Order: SVU or Bates Motel, both of which paint it clearly as abuse. But with the one-two punch of dramatic potential and mythical forebears, sibling incest is more common. (It’s established enough as a dynamic to have a network-friendly backup at the ready: take Lost’s Boone And Shannon Syndrome, where step-siblings present similar storytelling fodder without the full impact of the taboo.) Narratively, it offers several dramatic options: The context lends mythic weight, there’s built-in suspense in the often-illicit relationships, and sometimes the intensity of sibling incest imbues a nearly supernatural effect on the story around the characters. And the subtext or text of consensual sibling incest tends to signal siblings who are either of the elevated classes who have time for that sort of thing at a safe emotional remove from audience experience, and/or siblings who have suffered so deeply that the incest is a thematic signal that their only refuge is with one another. It’s a strange and distinctive uphill battle to be both unsettling and sympathetic.
Either way the story’s spun, the use of sibling incest usually suggests that something is somehow both very wrong and very interesting. Game Of Thrones has its share of such couplings amid its sprawling cast: Daenerys Targaryen comes from a family line famous for its Egyptian-style royal incest (and her brother seems as though he’d be similarly inclined if his lust for power wasn’t getting in the way of his other lusts). But for all the tragedy that follows that family tree, that incest is part and parcel of greater myths, since the Targaryens are also the most otherworldly of the ruling families: the dragon riders. The series’ more present-tense incestuous couple is Jaime and Cersei Lannister (twins—another powerful relation in many mythologies), who are a less rarefied depiction of the trope. Their passion is powerful but illicit, and neither one of them is a particularly good person: Throughout the first season, their only redeeming value is their love for one another and their connection after they’re parted and overcome by events. And things get even more emotionally complicated for them in the series than in the books, as an intimate reunion scene portrayed as consensual in the books was filmed as rape on the show. It takes that aspect of their relationship from a consensual one to something more abusive—which dismantles the delicate balance of a trope that requires everyone to be willing in order for sibling incest to be a story about a relationship rather than a crime.
Occasionally, a show will walk that line as close as it dares, leaning on the taboo to indicate destructive Byronic passion. The Originals has carefully chronicled the long and deeply twisted history of siblings Klaus and Rebecca, whose dynamic lands somewhere between codependence and abuse: Klaus has a history of murdering Rebecca’s lovers (“They come and go for her but I am the constant”) or “daggering” Rebecca in order to keep her half-dead and inert until the boyfriend in question loses interest or dies. The show makes their tension one of the major dramatic arcs of the show, winking at its own deliberate subtext: It only takes three episodes into the series before someone asks Rebekah if the man on her arm is “the infamous on-again-off-again?”, to which Klaus replies with suitable grim delight, “He’s the brother, actually.” But their relationship is also used to set them apart from other vampires, the implied incest creating a perpetual hunger no amount of blood can sate. It’s a feedback loop that’s perfectly suited to gothic horror—and supernatural circus-noir Carnivale used it between preacher Justin and his doting sister Iris both to indicate their shared downward spiral and to remind us just how important they were to one another.
But Carnivale was also aware of the horror underlying the gothic; with that undercurrent of darkness. When Justin and Iris cross the line from subtext to text, the moment is at best intense; at worst, it’s incest as the breaking of the trust between siblings—the antithesis of the mythic ideal of romance as extension of intimacy, not the fracturing of it. Incest qua incest is uncomfortable to audiences in either instance (as it’s designed to be); sympathetic incest rests on the idea of mutual love so overwhelming it becomes the only way the characters can attempt happiness. (It’s perhaps out of awareness of this fine line that Lifetime’s recent Flowers In The Attic adaptation handled the sexual frustrations of Cathy and Chris Dollenganger as if quietly pre-ashamed of itself, making sure its intimate scenes were both consensual and tame as a freshman-year play; the love scene is much less about the chaste kiss than it is about the pair of them discussing a life together outside the attic and realizing the broken truth so many TV incest relationships are based on: “I don’t know if I can ever love anyone else.”)
The Borgias has no such restraint. For two seasons, siblings Cesare and Lucrezia Borgia participated in Vatican scheming, suffered heartbreaks and betrayals, and trusted only one another; there’s so much romantic tension between them that characters can’t seem to stop commenting on it. (There are even mythical references, as during a Old Rome banquet at which Lucrezia dresses as Echo, the lonely woman doomed to fall in impossible love.) For two seasons the Borgias producers were clear that they weren’t going to cross the line into incest, and as Lucrezia suffered a humiliating marriage and Cesare chafed at the clerical collar, their mutually grim storylines were alleviated only by one another. It was enough bedrock that when the producers got word they’d be renewed for a third season but not a fourth, they threw caution to the wind and let Cesare and Lucrezia consummate the unspoken. And their established sexual relationship managed to complicate rather than diminish the siblings; they’d been close for so long, and so miserable apart, that the sex felt more like a relief than a taboo.
Their pairing was both passionate and relatively sanctioned by the show (Lucrezia speaks of God in the room with them as sincerely as any myth), and became the only emotionally weighty romance the show ever managed. They even had a love theme that began to overlap scenes of the show’s many political machinations, a reminder that this relationship was powerful enough to change the course of Rome—and their arc ended in a moment of such Byronic intimacy (as Cesare wipes her husband’s blood from her face) that it suggests the engine of their romance had pushed them past even their elevated status and made them somehow superhuman in their love for one another. It’s not a far reach; they had the advantage of being built up separately long before the relationship became text (so audiences got to anticipate the inevitable with more preparation than, say, Justin and Iris), but it also seemed as though, amid the Vatican scheming, incest between two loving siblings was as pure a love as anyone was likely to find.
Of course, that’s the trick about incestuous siblings, no matter where they fall. While incest can always be used as a neat shortcut to signal darkness or conflict, the mythic element of it actually rests on the subtext of the inexorable fate of those thwarted souls, which is almost always framed as outside the control of the siblings in question. On television, incest defines and directs the people in it in a way that occurs in very few other relationships; the happiness or sadness of a relationship of sibling incest is preordained by the narrative, and the characters powerless to fight against it. (They have to be, for this to work; no one chooses to break the taboo unless circumstances are somehow beyond their control.)
This is the essential storytelling trick that conjures enough sympathy to temper the inherent voyeurism of waiting for imaginary blood relatives to cross the line and kiss. And as the audience is asked to accept that the power of their feelings is strong enough to smash a taboo, we accept the underlying understanding that such closeness is only possible under awfully specific terms; a wrong thing, maybe, but also a rare one, and one that wields a power on the story greater than the sum of its parts. Cesare’s a sucker for Lucrezia and is willing to tear Italy apart to reunite with her; Justin and Iris are each other’s only true believers in a quest that comes with a body count, and Cersei and Jaime started a war trying to keep one another close.
Even when the text treats its lovers like villains—Lily and Caliban have few pleasantries to spare for one another and even fewer for anyone else—their sexual dynamic operates out of their control: their shared father means they’re acceptable only to each other. That loneliness and codependence is the foundation on which sibling incest rest: it’s a doomed inheritance from a rotten family. The lovers in question already know they’re tragic; under that sword, incest becomes both a self-destructive act of defiance against the inevitable, and a way to stave off tragedy a little longer. It’s a dynamic as narratively rich as it is discomfiting, and it’s not going anywhere.