“Weiner,” an astonishing, absurdist slice of political history about disgraced former New York congressman Anthony Weiner, opens with a quote from media philosopher Marshall McLuhan: “The name of a man is a numbing blow from which he never recovers.”

At the beginning of his career, Weiner was a rising star of the Democratic Party, not a human wiener dog. This masterful documentary shows how he made himself every bit as comical by unwittingly publicizing skivvies-clad photos of his namesake bulge.

There’s something irresistibly funny about that kind of defective judgment. It plays as if Weiner has a compulsion to put a “Kick Me” sign on his back and walk around America’s largest city. And the news media wore the world’s biggest shoes. What headline writer can resist “Weiner’s Rise and Fall”?

Filmmakers Josh Kriegman and Elyse Steinberg, who obtained behind-the-scenes access to Weiner’s laugh-and-cringe avalanche fall to public humiliation, treat the bizarre tale like a verite “Spinal Tap.” It’s a classic tale of hubris humbled, with a subplot of ratings-driven scandal coverage being marketed as journalism.

If you don’t recall, Weiner created a media firestorm with a “sexting” scandal in 2011 while his wife, top Hillary Clinton aide Huma Abedin, was preparing for the birth of their first son. Using the code name “Carlos Danger,” he publicly tweeted a partly clothed photo of his male endowment. He meant to send it as a direct message to a young woman his wife didn’t know. That cyber slip-up made Weiner a figure of comic flogging by Stephen Colbert and many more, a punch line who triggered gales of laughter at the mention of a staff meeting.

After first denying it, then confessing, resigning, apologizing to his constituents and taking therapy to repair his marriage, he launched another electoral run. In 2013 he became a New York City mayoral candidate, hoping to rejuvenate his reputation, and intending to win. He started out surprisingly well. And then he torpedoed himself again, sending bawdy phone-message photos of his not very private parts to female fans. Which triggered another crisis, as one of his online lady friends, a Las Vegas card dealer named Sydney Leathers, joined the media brouhaha for a burst of publicity to help her transition to her dream job as a porn star.

The film is impressively neutral, taking an unprejudiced view of precisely who the villains and victims of the piece are. This fly-on-the-wall view of Weiner’s imploding political career is a movie that would be tragic if it weren’t so goofy. Running a taut 97 minutes, it’s the must-see nonfiction film of the year.