The spooky (and sweet) history of fake blood

This spooky season, as you binge horror flicks, peep the Halloween décor, and peruse potential costumes, pay attention to the fake blood and you’ll notice something odd: It all looks wildly different. Sometimes it’s an almost cartoonishly bright red, and at other times it’s dark brown, bordering on black. Some of it’s thin and watery, and some is viscous and goopy. 

That variation isn’t a byproduct of carelessness or confusion. Real human blood is a dynamic substance. Its hue changes according to the amount of oxygen it contains, and as it ages and breaks down. Its thickness and flow vary with the concentration of key proteins within it, or the environment it’s in. It clots and coagulates, often quite rapidly. And anyone making fake blood needs to consider not only how these biological variables line up with the scene they have in mind, but also the practicality of working with a given recipe, how it’ll look from a distance, and the impact it’ll have on a viewer. Artists and prop masters have grappled with these complexities for ages. Understanding the arc of that quest may help all of us better appreciate—or make our own—fake blood.

The earliest examples of fake blood, from red cloth to glycerol goo

Some folks believe that the pre-modern cultures simply used actual blood in plays and tableaus, for maximum verisimilitude. That’s unlikely, as the real deal wouldn’t keep well if you wanted to save it for a scene, and would create cleanup nightmares. Instead, early actors and prop makers probably just pantomimed bloodless violence, at most using bright red cloth to signify gore. 

Inventive prop makers undoubtedly experimented with other stand-ins for blood over the centuries, like splashes of red paint. But the first clear records of an established, dedicated fake blood formula appear in accounts of shows at the Grand Guignol, a Parisian theater that specialized in the late-19th-century equivalent of splatter films. We don’t have an exact recipe, but they seemingly used glycerol or propylene glycol—clear, viscous liquids used in foods, cosmetics, and industrial processes—and bright pigments for a thick, pooling, vibrant crimson goo. This garish blend might not have been convincing up close, but it worked for gawkers in the cheap seats, and with the theater’s bombastic ethos. 

Alfred Hitchcock, black and white films, and the rise of chocolate syrup

Social taboos, censorship concerns, and technical constraints limited the use of blood in less bawdy theaters—and in most early films. At most, directors would flash to “a small trickle of black or a smear,” usually made of some oily substance cut with a dark pigment, explains Gregor Knape, a special effects makeup artist and SFX history buff. 

But a few black and white directors used chocolate syrup instead. The dark brown didn’t wash out like bright hues in early cameras’ filters, and its viscosity and flow is eerily similar to a thick line of fresh blood. Alfred Hitchcock notoriously used a recent innovation, the plastic squeeze bottle, to give the blood in Psycho’s (1960) shower scene a realistic drip and splash effect. 

Hitchcock later explained that he opted to film in black and white both to cut costs, but also because he thought color blood would be too gory for most audiences. Yet in reality, Knape explains, early color filmmaking methods didn’t do well with semi-clear substances like (pseudo)blood, or with muted colors. So throughout the mid-20th century, filmmakers had to use “opaque and almost garish raspberry red” fake blood mixes, Knape explains. Hammer, the prolific British horror studio that helped launch Christopher Lee’s career, notoriously popularized the use of “Kensington Gore,” a fake blood blend with the hue of cherry syrup. 

“Blood in 1960s cinema almost always looked better in black and white,” argues Blair Davis, a film scholar who specializes in older horror cinema and low-budget “b-movies.” 

Fake blood in color films

Prop makers striving for realism and nuance chafed under the restrictions of early film technology. So when new color filming systems came on the market in the mid-1960s, they jumped on the chance to try something new, says Knape. Herschell Gordon Lewis, a softcore pornographer turned godfather of modern gore movies, famously balked at the cartoonish blood on the market when he started making Blood Feast (1963), America’s first splatter film. So he commissioned a pharmacist to make him a more subdued and translucent blend. However, Lewis was notoriously cheap, so while his new blood was a step towards realism, it wasn’t super sophisticated.

After a few years of industry-wide experimentation, often riffing on the recipes for Guignol blood and Kensington Gore, the legendary makeup artist Dick Smith developed a formula using Karo (a common brand of thick, caramel-colored corn syrup), a colorless preservative called methyl paraben, food coloring, and Kodak Photo-Flo, a substance used to prevent streaks on photos during development, to create a hyper-realistic fake blood. If you’ve seen The Godfather (1972), The Exorcist (1973), or Taxi Driver (1976), then you know exactly what Smith’s blood looks like.

Prop masters soon realized they could make simple tweaks to Smith’s core recipe to adjust color and viscosity, matching the biology and environment they wanted to represent. Darken and thicken it for old and scabby goop. Brighten it for a fresh oxygen-rich arterial spurt. (Martin McDonagh’s The Lieutenant of Inishmore used nine different blood blends for situational variety.) Some also tweaked the formula to meet more practical needs, like cost and edibility. The team behind The Evil Dead (1981) notably swapped out the paraben and Photo-Flo for non-dairy creamer, sacrificing a bit of fidelity and viscosity to shove gobs of their blend into cast members’ mouths then “barf” it out or let it dribble down their chins. 

“From that time on, most fake blood products have been variations on a limited range of ingredients,” Knape explains. Even popular Halloween recipes mirror Smith’s, likely because he made it a point to publish accessible DIY how-to guides for aspiring prop makers of any sort. 

The 21st century’s computer generated gore

Around the turn of the millennium, filmmakers turned to CGI to augment their fake blood, adjusting the colors or make their splatter physics a little more convincing. Some have moved away from prop blood entirely, in pursuit of full control and detail. Like most CG effects, when done badly computer-generated blood looks either comical or uncanny. But when done well, it’s an incredibly effective stand-in for the real deal.

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However, not everyone is aiming for gold-standard realism in their blood. On the practical side, filmmakers, prop masters, and costumers sometimes tone down their blood to make it more palatable for mass audiences—or just for film rating agencies. Or they’ll use a less realistic blood, Knape explains, because they want something more visible on a dark background, or especially easy to clean. (This is yet another reason many filmmakers appreciate fully CG blood.)

If a creator wants to evoke a particular emotion, Davis adds, they might favor something stylized and surreal. When making the Kill Bill duology, Quentin Tarantino stressed the importance of using different blends for different visceral-emotional effects, drawing a particularly stark line between “horror movie blood” and “samurai blood.” In the end, the fake blood you see may be less about the quest for realistic gore and, as with old Guignol blood, more a matter of practicalities and vibes. 

Given all the different factors directors balance—the type of blood they’re depicting, the practical limits they’re working under, the effect they want to have on an audience—every example of fake blood you see is probably going to be a little different, Knape argues. Makeup artists don’t tackle every project using the one true blood they believe in, he adds. They start with several formulas, test them out under different conditions, and trial-and-error their way into the right blend for each task.   

So if you’re pondering your own Halloween costume and decor right now, don’t worry too much about the fake blood you’re using. Just use what feels right—what brings you joy. Then have a bloody good time. 

The post The spooky (and sweet) history of fake blood appeared first on Popular Science.

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