It was pure happenstance that led West Tisbury cartoonist Paul Karasik to stumble upon a mural last fall that would become the basis of his first essay in The New Yorker magazine.

Mr. Karasik has had numerous cartoons in The New Yorker but never an essay. This past fall he was a visiting professor at Penn State University and headed to a meeting with a colleague at a Starbucks, located in the university library. His counterpart said to look for him at the Addams mural, a 14-foot work by influential 20th-century cartoonist Charles Addams that features the famously macabre Addams family making a trip to the beach.

Mr. Karasik, who frequented the coffee shop and is an avid fan of Mr. Addams’s work, said he couldn’t believe it and began investigating.

“I thought he was making a joke,” said Mr. Karasik. “Nobody knew it was there.”

Mr. Karasik said the mural was hidden away behind a security desk and encased in glass due to damage sustained from a coffee cart spill. It was originally painted for a bar in Long Island, but when the bar switched owners the mural was gifted to the university. Over the years it moved from the university museum to the library to the side entrance of the library. And now, with the library scheduled to be renovated, its future was uncertain.

Mr. Karasik began taking notes on the history of the work and deconstructing the image, with the idea that he would publish the piece in the Penn State alumni magazine to draw attention to it before the library began its renovation.

“The reason why I wrote this article was really to save this mural from being put in storage or sold,” he said. “This is a masterpiece of comic art by probably the single most influential New Yorker cartoonist.”

Mr. Karasik said he was about to send an email to the Penn State magazine when he had the idea to send the piece to The New Yorker instead. The Addams cartoons had been a mainstay in The New Yorker since they first appeared in 1938. The mural is the largest ever painted by a New Yorker cartoonist.

The first editor he sent it to passed on the essay. He approached another editor, who said yes.

The piece appears in the double issue (July 9 and 16) edition of the magazine under the headline The Addams Family Secret. It currently can be viewed in its online version, which features an interactive graphic of the mural where Mr. Karasik points out how the elements of the painting come together to make the viewer respond to it.

To Mr. Karasik, who said he has hardly missed reading a New Yorker cartoon since he was a kid, getting a writing byline in a magazine with such a rich history of cartooning was a dream come true.

“I have a published piece in The New Yorker,” he said. “It’s a miracle.”

Paul Karasik will be teaching a weeklong graphic novel workshop for ages 15 and older, including adults, from July 9 through July 13 in Vineyard Haven. The cost of the class is $500. To register, email paulkarasikcomics@gmail.com.