



The slasher flick will take yet another stab at the cineplex next week when Scream 4 , the latest installment of the 15-year-old franchise, hits theaters. As any fan of the series knows, slashers—that ‘70s-born genre about sociopaths wielding pointy objects and punishing teen fornicators—follow a particularly well-honed set of rules: The killer is usually male, coitus is usually interruptus, and only the virginal “final girl” will survive. That formulaic nature extends to sequels as well. As the series’ resident film scholar Randy noted the second time around, “There are certain rules that one must abide by in order to create a successful sequel.” Rule No. 1? “The body count is always bigger.”



Is that really true? We decided to examine the relevant data. Above you’ll find a chart (splatter plot?) graphing body counts in slasher films by franchise and year of release. (Technically, the Saw films aren’t slashers—they’re torture porn—but we’ve included them for reference. You can see a spreadsheet with our compiled data here.)



Turns out Randy was right: The higher a film’s sequel number, the bigger its body count. The first film in a series tends to leave behind only five to 10 victims, while, in successive entries, corpses pile up at increasingly alarming rates.



You might think that slashers have just become more violent over time. But it turns out that the number of the sequel is more significant than the year of the film’s release. The first three Scream movies, for example, knock off teens at approximately the same rate as the first Halloween and Friday the 13 th movies did 15 years earlier.



There are some exceptions to the sequel rule. Reboots, for example, often rein in the death tolls to levels just above that of the original film. (See, e.g., 2009’s Friday the 13 th , in which Jason machetes only 13 campers—about 11 fewer than in the previous film.) Randy posits a similar exception in Scream 3: “If you find yourself dealing with an unexpected back story and a preponderance of exposition, then the sequel rules DO NOT apply… You are not dealing with a sequel, you are dealing with the concluding chapter of a trilogy.” These days, any good slasher series gets stretched well beyond three movies, but I’ll take his point on confidence.



With these factors in mind, here’s our highly sophisticated working formula for predicting that magic horror movie number. Let B be defined as “body count”:

B = 2n+12(Z-R)+2c+2S+3



B = Approximate onscreen body count

n = The number of the installment in the series

Z = Zombie factor (i.e., is the film directed by rock-’n-schlock auteur Rob Zombie? 1 for yes, 0 for no)

R = Is the film part of a reboot? (1 for yes, 0 for no)

c = The number of colons in the title

S = Does the film take place in outer space? (1 for yes, 0 for no)



Here are a few examples of the equation in action:



- Seed of Chucky (2004) is the fifth (and so far final) Child’s Play film, giving it an n of 5. It’s neither a reboot, a film directed by Rob Zombie, an installment with colons in the title, nor a chapter in outer space, so Seed ‘s body count (2(5)+3) is correctly predicted to be 13.

- Jason X (2001) is the tenth Friday the 13 th film (though the filmmakers insist that the X does not stand for “ten”). It also takes place in space. 2(10)+2(1)+3=25, and while Space Jason’s personal kill count is only 22, 25 people die in the film.

- Halloween H20: 20 Years Later (1998) is Halloween ‘s first reboot (it ignores the storylines developed in Halloween films three through six) and the seventh installment in the franchise (n =7, R=1). It has one colon in the title, is not directed by Zombie, and does not take place in space, so its predicted body count (2(7)-12+2(1)+3)) is 7—which, if one counts the paramedic accidentally decapitated by protagonist Laurie Strode, is indeed the death toll.

- Halloween (2007) is the ninth Halloween film (n =9). It’s a reboot directed by Rob Zombie, so Z and R cancel each other out. C and S are zero, so the film’s predicted body count is 2(9)+12(1-1)+3, or 21. Michael Myers notches 18 kills in the theatrical release, there are 20 casualties total in the theatrical cut, and there are 22 in the unrated cut, so a predicted 21 ain’t bad.



We ran this equation on all the slashers in our data pool , and in each case the predicted body count was within four of either the body count from the killer or the total body count.



Using this equation, we predict that Scream 4 will have a body count of 11—just a notch above Scream 2 and Scream 3, but not the huge leap that occurs when, say, a franchise attempts to revitalize itself by moving the action off-planet. So if you’re a slasher fan with a massive bloodlust, we suggest skipping Scream 4 and instead holding out for the inevitable Chucky Part XI: Dolls in Space: A Rob Zombie Film (predicted body count: 43).



What factors would you use in a body count equation? And what other puzzles might be solved with a little cinemalgebra?



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