Why "bad seed" films are both deeply unsettling and confoundingly popular.

Hypothetical question: What if a parasitic creature is squatting in one’s womb? What if, once born, the baby is a monster—alien and unlovable? What exactly does one do if the darkest and most unspeakable of parental fears come to terrifying fruition? These questions drive one of the classic tropes of horror: the bad seed film. Lynn Ramsay’s We Need To Talk About Kevin, a psychological thriller about the relationship between Eva (Tilda Swinton) and her sociopath son, is the most recent addition to a genre that is both deeply unsettling and confoundingly popular.

In order for a film to legitimately be called a bad seed picture, it must have a strong parent-child element, and the "parent" is almost always the mother. Maternal guilt and culpability is the engine that keeps these films running, and generally, the father is at best haplessly naive and at worst complicit in the child’s misdeeds. And, as opposed to a film like Children of the Corn, in which evil children operate horrifically outside of the bounds of adult control, the bad seed movie gives us little monsters who are, at least nominally, under parental supervision. A viewer prone to identifying with characters in films, even bad horror movies, doesn’t feel sorrow over the death of lil’ Isaac, the crazed killer prophet from Children of the Corn, because his death represents the death of an aberration: a psychotic, parent-killing monster. In the evil spawn films, though, there can be no return to normal—one way or another, the order has been upended, and there is no way for these plots to end in a satisfactory manner for either the child or parent.

The bad seed genre can be divided into three general types:

1. The Perfect Aryan Psychopath. Reflecting cold-war paranoia and fears of genetic pre-determinism and juvenile delinquency, films like The Bad Seed and Village of the Damned present children whose evil is beyond the influence of parents. The Bad Seed gives us Rhoda, an entirely evil little girl in an entirely perfect package. Though she looks like a model of ’50s girlhood, (pressed dresses! blond braids!), she has inherited her grandmother’s "bad seed" and is thus genetically destined to be evil. Her mother still takes the blame, obviously, since there is no real father in the picture (which is also clearly the mother’s fault), and it’s the maternal side’s genes that make Rhoda kill.

Dramatic endings for this kind of movie tend to be kill your child/let your child die. In The Bad Seed, upon finding that little Rhoda is, in fact, a rampaging serial killer, the mother attempts a murder-suicide. Though she succeeds in killing only herself in the novel and play versions, film censors demanded a different ending: Rhoda is struck by lightning while her mother recovers from the suicide attempt. This is supposed to be an ending that reinforces the Hayes Code edict that “crime doesn’t pay”: A mother surviving the death of her child (after trying to kill her) somehow re-rights the status quo.

In The Village of the Damned, the little Aryan children (again, nothing creepier than perfect little blondies!), though born of human women, are really alien spawn. Our hero initially tries to work with the children (stupid liberals, always trying to reform obviously evil children!), but soon realizes that only bombs will do the trick. A more recent example of this type of film is The Good Son, in which Macaulay Culkin appears to be, well, Macaulay Culkin, and is in fact a murdering lil’ psycho. While The Good Son never blames evil genes, it rejects the accepted psychological wisdom. In real life, most violent people come from violent households or have suffered trauma or violence in their formative years. In The Good Son, Culkin lives in a warm, supportive family, instilling in viewers the old bad-seed idea that when a kid is evil, no amount of nurture can undo malevolent nature.

2. Hell-Spawn. In the late ’60s and ’70s, the bad-seed genre saw the advent of the literal hell-spawn picture. In movies like Rosemary’s Baby and The Omen, the child is not really a child at all, but the product of witchcraft, satanic rituals, and/or some very shady baby-making. Aside from reflecting the fears of a tumultuous era that veered toward end-times paranoia, the hell-spawn picture is especially hard on the mother characters, as your options are few when siring Satan Jr.

Essentially, the parents have two endgames in this kind of movie: Die, and let your child do as he will (in The Omen, Gregory Peck is killed before he’s able to kill Damien), or accept that you are Satan’s mother, and get to nursin’! In Rosemary’s Baby, once our poor Rosemary realizes that she has unwittingly birthed the Antichrist, what are her options? Can she really kill her own offspring? No. Can she relinquish all parenting responsibilities to her Satan-worshipping neighbors? No. So Rosemary drops the knife and picks up her baby. She has been used as a human devil incubator, and she is now trapped by motherhood, a prisoner to maternal love and responsibility. The mother is abject before her monstrous child, unable to control, trapped by maternal love and expectations.

3. The monster takes after his mommy. What if that terrible child is not some completely foreign demon, spawned of the underworld? What if the child is recognizably part of you, a being filled with your malevolence, your violence, your anger? And what if you instantly recognize the child as such, and fear and dislike your child? This is the far more chilling premise at work in We Need To Talk About Kevin.

Based on Lionel Shriver’s novel of the same name, We Need To Talk About Kevin is the story of a boy whose mother suspects her child is evil long before he commits the story’s horrific acts. Shriver’s book and the film are both presented from the perspective of the mother, Eva, and posit that Eva’s ambivalence about motherhood may be responsible for Kevin’s malevolence. And so We Need To Talk About Kevin takes maternal anxiety to its most horrific extreme: By being at all unsure about motherhood, one is inviting a sociopath son, a child who will somehow "know" he is not loved enough by his mother, and will by virtue of this, become a monster. It’s all, ultimately, the mother’s fault.