Devlin's Angle

February 2005

NUMB3RS gets the math right

If you've read the January 21 issue of Math Games by my fellow MAA Online columnist Ed Pegg Jr., you will have some general background on the new CBS prime-time television series NUMB3RS. (Ed also includes some cool photos from the show.) Normally, columnists try to avoid covering the same story, especially within a couple of weeks of one another, but the launching of a major television series in which the hero is a mathematician is such an unusual event that it surely merits a second look.

For one thing, successful movies or television series have in the past led to a significant upsurge in the numbers of students who opt for various majors at university. Perhaps the most cited instance of this is the large number of AI practitioners who were first inspired to enter the field by the 1968 movie 2001. And I'm told that criminal forensics got a huge boost as a potential career as a result of the TV series CSI.

More generally, surely almost anything that can improve the image of mathematics in the population at large deserves the support of the mathematics community.

The widespread ignorance among the general public of what mathematics is all about is testified by the fact that one of the criticisms of the new series after the first episode was screened on January 23 was that it defied credulity. Many TV critics, it seems, could not believe that mathematics could be used to help solve criminal cases in the way depicted in the program. Yet that first episode, like all the other upcoming episodes in the first season, is based on a real-life case. Not just loosely based on it, but closely so.

[It's amusing to note that "NUMB3RS doesn't add up" was the most common comment among the several dozen newspaper reviews I looked at, an oh-so-obvious choice of phrase that was ironic given that one of the critics' main complaints was that the series lacked originality and adopted a tired and over-used formula!]

I got the inside scoop on the new series shortly before it first aired, when I met with the series' co-creators, co-producers, and co-writers Nick Falacci and Cheryl Heuton. Their starting point, they told me, was to develop a prime-time television series that featured mathematicians and scientists. At the back of their mind was the late Richard Feynman, the famous physicist at their local university: Caltech. But getting a major studio to commit to a new idea, especially one involving math, was, they discovered, no easy matter. Their solution - which was clearly very successful in terms of getting superstar movie and TV producers Ridley and Tony Scott (whose movie credits include Alien and Top Gun, respectively) to produce the series and CBS to buy it - was to fit their idea into a tried and tested formula: the police procedural detective series.

And so, eventually, NUMB3RS was conceived, a variant of the hugely popular CSI series, with the forensic scientists of CSI replaced by mathematics genius Charlie Eppes, who gets involved in cracking criminal cases through his elder brother Don, an FBI agent.

For the pilot episode, Falacci and Heuton chose a serial rape case that arose in Louisiana in the late 1990s. In that real-life case, a Canadian police detective with a Ph.D. in mathematics read about the case and wrote to the local police to offer his services. He had, he said, developed a formula to determine the likely residence location of the perpetrator, based on the pattern of locations of the crimes.

By then, the local police were willing to try anything, and so they brought the Canadian detective onto the case. What happened next will be familiar to you if you watched the first episode of NUMB3RS. The police scoured the likely residence location determined by the mathematics formula, collecting DNA samples from cigarette butts and other castaway items of all males in the area, and had those samples tested against those from the rape victims.

In the event, none of the samples collected matched, until someone wondered if the perpetrator had recently moved. (Yes, even that part of NUMB3RS was taken right from the real-life case! Why make things up when real life has all the dramatic elements you need.) Thanks to the mathematics, the (real-life) criminal - a police detective as it turned out - was caught.

The mathematical formula you see actor David Krumholtz (who plays the mathematician) write on the blackboard in his home is in fact the equation used in the real case. The other equations you see (and will see) in the series, including the water sprinkler example near the start of episode 1, were written by the series' principal mathematics advisor, Gary Lordon, the head of mathematics at Caltech, by mathematics graduate students at Caltech, and by other professional mathematicians, a great many of whom the series producers have contacted to ask for help. (They sent a representative to the Joint Mathematics Meetings in Atlanta last month, to extend their network of contacts in the profession.) So much for all those TV critics who thought the plot was too implausible!

The second episode, which was broadcast on January 28, is based on a real life series of bank robberies in Maryland last year. In that case, a mathematician in Arkansas provided the pattern analysis that resulted in the police lying in wait at the bank when the gang struck.

Will the new series be a success? No one knows, not even the heads at CBS who commissioned it. Twenty-five million people watched the first episode, by far the largest of any new TV series this season (Desperate Housewives had garnered 21.6 million), no doubt helped in large part by being screened right after the NFL Super Bowl playoff game between the New England Patriots and the Pittsburgh Steelers. But even without the football, the 17 million viewers who tuned in to the second episode the following Friday night made that the most watched program of the evening.

If the series does go down the tubes after a few episodes, it won't be because the math is wrong. The producers have gone to great lengths to get the math right. (They also have a real-life FBI agent on the set to make sure the police stuff is correct as well.) Nor is Krumholz's portrayal of the math genius off the mark. Okay, he's cuter than most of us, but looks apart, his character seems to me like an amalgam of a half dozen mathematicians I have met. (In preparing for the role, Krumholz hung around Caltech for a while, seeing what real mathematicians are like.) Sure, the writers and the actors employ dramatic license in their portrayal of mathematicians and what is involved in doing mathematics. This is, after all, a prime-time television crime series, not a mathematics lecture or a documentary about mathematicians - neither of which could come close to drawing a television audience of 25 million, even if they followed the Super Bowl final itself. But at heart they get the mathematician and the math right.

Failure of the show is also unlikely to result from viewers being put off by the math. When CBS tested an early version of the pilot, the sample audience was not only intrigued by the math, they said they wanted more of it in the show! Similar highly positive responses to the dramatic portrayal of mathematicians and mathematics followed both of the stage plays Breaking the Code and Proof and each of the movies Good Will Hunting, Pi, and A Beautiful Mind.

For my part, I hope the show is a success. True, I watched the first episode and am following the series purely because of the mathematics angle. I confess that I rarely watch TV, and have never seen a single episode of CSI. (Not because I have anything against TV. I just never seem to have the time to switch it on! Maybe I spend too much time writing MAA columns.) But if NUMB3RS does make it, it could do wonders for the general perception of mathematics among the general public, and perhaps stimulate more young people to go into the field.

And maybe one day, TV critics and others will not be surprised and incredulous when they learn that math is used in different ways in many walks of life.

You can listen to a brief radio discussion on NUMB3RS between Keith Devlin and host Scott Simon on NPR's popular magazine program Weekend Edition, by clicking here.
Devlin's Angle is updated at the beginning of each month.
Mathematician Keith Devlin (email: is the Executive Director of the Center for the Study of Language and Information at Stanford University and The Math Guy on NPR's Weekend Edition. Devlin's newest book, THE MATH INSTINCT: Why You're a Mathematical Genius (along with Lobsters, Birds, Cats, and Dogs), will be published in April by Thunder's Mouth Press.