Hillary Clinton’s campaign chairman may have lost his handkerchief on Martha’s Vineyard one day in September 2014 – and two years later that incident has spawned a convoluted conspiracy theory involving a supposed pedophilia ring run out of a Washington, D.C., pizza joint.

How we got from John Podesta’s hankie to claims of a child sex ring – and an armed man arrested Sunday at the pizza parlor attempting to “investigate” the claims – is a disjointed tale that reveals how a toxic Internet story is born, fed and spread without evidence.

Edgar Maddison Welch, a 28-year-old North Carolina man, was arrested Sunday afternoon on a charge of assault with a deadly weapon, after police say he fired his rifle into the floor of the pizza place. No one was hurt, but the incident sent customers running. Welch, who told authorities he went to the establishment to “self-investigate” the sex ring claims, allegedly was spotted looking for rumored tunnels filled with hidden children, a nearby store owner told The Washington Post.

MAN WITH RIFLE ARRESTED AT DC EATERY

Welch apparently was searching for proof of the so-called “#pizzagate” plot, initially advanced by users on 4Chan and Reddit on Nov. 4, citing seemingly innocuous details from Podesta’s hacked emails as evidence of a child sex operation.

The author of one popular blog that gathered many of the details pointed, for instance, to the 2014 email to Podesta about a supposedly missing handkerchief. The blog claimed the description of the cloth as “white w/ black” correlated to a “handkerchief code” indicating leanings toward “S&M” and “Virginity/Pedo.”

The handkerchief was described in the email as “having a map that seems pizza-related.” Podesta referred often in his emails to pizza – a popular dish for anybody, never mind hungry and overworked campaign staffers. But the numerous mentions merited a deeper look for some. And that brought them to the pizzeria that Welch walked into on Sunday: Comet Ping Pong.

Comet Ping Pong has been a popular eatery for a decade. Its walls are painted with trendy murals and its owner, James Alefantis, was ranked No. 49 in GQ’s 2012 edition of the 50 most powerful people in Washington.

But to posters on 4Chan and Reddit, the murals contained disguised symbols of pedophilia. It was even posited that Comet Ping Pong’s logo had Satanic connections. Alefantis’ personal social media postings, which contained popular memes and pictures of family and friends, were dissected for alleged links to the sex scheme. This included an Instagram image of a girl with her arms stuck with masking tape to a table, with a comment joking about it being a “procedure for your youngest guests.” His fundraising links to key Democratic figures – including Podesta – were also cited as proof.

Alefantis was a sender or recipient of about 20 of the more than 50,000 leaked Podesta emails, with messages dating between 2008 and 2016. In one October 2008 email, Alefantis wrote to Podesta following a fundraiser: "Raised over 40 grand. My only regret is I did not make you a nice pizza. When can I?"

The conspiracy theorists claim "pizza" is a euphemism.

As far-fetched as "#pizzagate" is, Bill Clinton's past helped fuel the theorists. The former president – aside from having acknowledged extra-marital encounters and having been accused of sexual assault by several women, which he denies – flew several times on the private jet of Jeffrey Epstein, a wealthy financier who was convicted in 2008 of soliciting prostitution from an underage girl. For some Redditers, it was a simple act of connecting some very, very distant dots to get from there to Comet Ping Pong.

But even after the election, the controversy refused to die down. Questions about “#pizzagate” persisted on Twitter and Facebook. Believers journeyed to the pizza place, posing questions to Alefantis and streaming Facebook Live videos. Finally, an armed man arrived.

Though the “#pizzagate” conspiracy was widely shared by far-rightwing elements on the Internet who supported Donald Trump and distrusted Hillary Clinton in the run-up to the election, it was also spread by others. The author of the popular blog about “#pizzagate” is a self-proclaimed supporter of Sen. Bernie Sanders, I-Vt., who claimed to vote for a third party on Election Day.

The son of incoming National Security Adviser Lt. Gen. Michael Flynn, also named Michael Flynn, tweeted about Welch’s arrest on Sunday night: “Until #Pizzagate proven to be false, it’ll remain a story. The left seems to forget #PodestaEmails and the many ‘coincidences’ tied to it.”