Seinfeld is one of those classic comedies that everyone has watched, either in its initial run in the 1990s or in its unending syndication. Perhaps the show's most memorable secondary character is Newman, Jerry Seinfeld's scheming nemesis and Kramer's longtime friend. Played by Wayne Knight, the postal worker was usually little more than an irritant who was easily avoided.

However, a new fan theory proposes that Newman wasn't simply a muffin top-eating annoyance with an evil laugh, but an actual serial killer -- at least, at some point in the past. It sounds more than a little ridiculous, but the idea actually has some convincing evidence.

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SYMPATHY FOR THE DEVIL

In the episode "The Diplomat's Club," Kramer asks Newman to bring over his mailbag worth thousands of dollars as collateral for his gambling. Of course, the bag isn't just any old mailbag; it actually belonged to David Berkowitz, the serial killer more famously known as the Son of Sam" During the summer of 1977, Berkowitz murdered six people and wounded seven others. All of New York City went into a frenzy as the police tried to hunt down the elusive killer. Once captured, Berkowitz claimed that his neighbor's dog spoke to him and motivated his murder spree, although he later claimed that story was a hoax.

That makes one wonder what Newman was doing with Betkowiz's bag. One of the explanations is that they were actually friends before the killer was captured, and maybe even worked together at the U.S. Postal Service. At one point, Newman even jokes about dogs speaking to him while he's on his mail route.

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SECOND SON OF SAM

This is where things start to pick up steam. The theory proposes that Newman was not only Berkowitz's friend but actually his accomplice, either aiding Berkowitz with the murders or killing people himself in the name of the Son of Sam. It's possible Berkowitz may have taken Newman under his wing and trained him as a serial killer.

However, once Berkowitz was captured, Newman either chickened out of any further crimes or potentially lost interest in murdering people. The only memento he kept from his serial killer days was the bag. According to the theory, Newman kept it around because it offers sentimental value, as well as a reminder of his days where he got away with murder.

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The theory also notes similarities between Newman and Berkowitz, such as  mannerisms and habits (Newman and Berkowitz each responded to the police coming to arrest him by saying "What took you so long?"). However, the most compelling piece of evidence is that Newman does fit many elements of the serial killer profile. He is spiteful, resentful toward women, obsessed with getting back at his singular enemy (Seinfeld), egotistical and, on top of everything else, just really strange. These are elements of the serial killer profile that also align with Berkowitz's profile.

KRAMER KNOWS, TOO

Of course, it would be absurd to think Newman, who laughs maniacally at the drop of a hat, could conceal his criminal activities. While the Seinfeld cast knows a lot of strange characters, surely Jerry & Co. would notice if Newman were a serial killer. Well, the theory proposes that someone did know.

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Let's return to Berkowitz's bag, which was worth a great deal of money -- enough to help Kramer use it as collateral for a double-or-nothing bet. Newman doesn't hesitate to respond to Kramer, because his acquaintance has something on him. That dirt might just happen to be information about a series of murders.

HOW PLAUSIBLE IS THIS SEINFELD THEORY?

Jerry, George, Kramer, and Elaine in a jail cell in Seinfeld finale

While this theory is entertaining, and goes a long way to explain the character, Newman would be unable to keep his mouth about his evil schemes. He is seen using his position as a public servant for many self-serving plots, but, ultimately, Newman is more interested in making his life easier than anything else. Given his desire to destroy Seinfeld, one would think that, if Newman had murdered people, he'd ensure Jerry was among his victims.

But the biggest hole in the theory is that, beyond knowing Berkowitz, there is no evidence that Newman ever killed anyone. He has committed plenty of illegal deeds over the course of the series, many of which undoubtedly rise to the level of federal crimes. While there are jokes throughout Seinfeld about mail carriers "going postal," Newman never actually flies into a murderous rage. (In fact, in the episode "The Junk Mail," Newman is cowed when apprehended for questioning in connection to Kramer's plot to stop receiving mail.) More often than not, he simply launches into a villainous soliloquy. While Newman certainly fits some elements of the serial killer profile, he's no Berkowitz.

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