Pinning down the surgical details about Vincent van Gogh cutting off his ear may seem like a ghoulish quest.

Bernadette Murphy, who spent years doing just that, says it turned into something considerably more insightful.

In Secrets of the Dead: Van Gogh’s Ear, which airs at 10 p.m. Wednesday on PBS (check local listings), Murphy says filling in the details of that infamous self-mutilation “really enables us to understand the tragic story behind it.”

The basics of the story have shaped public perception of Van Gogh over the past 130 years, even as the paintings he couldn’t sell in his lifetime were becoming increasingly iconic.

On the night of Dec. 23, 1888, in Arles, France, Van Gogh took a razor and sliced off some part of his ear. The whole ear, some said. Just the lobe, said others.

That act, even more than the suicide he would commit 19 months later, stamped him as a classic deranged genius – a perception Murphy says is largely true.

“By late 1888 he was on the brink of insanity,” she says, and then he was hit with a one-two punch of further terrible news.  

His brother Theo, who had always supported him, was getting married, which Vincent feared would take Theo away. At the same time, Van Gogh’s fellow artist Paul Gaugin, who had moved to Arles in what Van Gogh dreamed would become the start of an artists’ colony, said he was leaving.

That probably shouldn’t have come as a surprise to Van Gogh, since he and Gaugin had turned out not to be very compatible. Gaugin had written to friends that he found himself living with a madman.

Van Gogh’s world, never very stable to begin with, was imploding.

So he picked up the razor and hacked off his ear. He then wrapped it up and brought it to a prostitute he knew in town, telling her this was to remember him by. He returned home and passed out, to be found the next day in a pool of blood.

The incident was reported in the local papers, so there was documentation. But there were conflicting reports on details like the extent of the injury, and that’s what caught Murphy’s attention.

“I’ve always been a curious person,” she says. “I was not an intense fan of Van Gogh, but I felt there had to be a story here.

After extensive research, the British university professor was still missing one essential piece of evidence: any report from the doctor who treated Van Gogh.

The Van Gogh museum in Amsterdam had nothing. Neither did other researchers. But Murphy finally found a trail that led her to the Bancroft Library in California, where librarian David Kessler dug out uncataloged papers saved decades earlier from author Irving Stone’s research on the Van Gogh biography Lust for Life.

Those papers included the doctor’s sketch of the amputation.

That was in 2010. Murphy spent the next six years filling out further details and writing a book on which this Secrets of the Dead episode is based.

Secrets of the Dead is framed with a certain ominous melodrama, particularly musical, but Murphy says the integrity of her research and findings remains.

In fact, she says, there’s a strong secondary lesson in this story, “which is the value of going out and doing actual research, not just copying what you find on the Internet.”

In the course of that research, she adds, she did become more of a Van Gogh fan.

“The more you know of his story, the more impressive his work becomes,” she says. “He created so much great art almost in spite of himself.

“We also see how his work was evolving into post-impressionism at the same time he was going crazy. He was one step away from the asylum.”

Van Gogh always had a strong self-focus, reflected in the numerous portraits he painted of himself. Soon after the ear incident he painted another, prominently showing a bulky white bandage down the side of his face.

“Painters must be selfish,” says Murphy – and Van Gogh is only an extreme example of an artist whose obsessive and unstable personality doubtless contributed to some of mankind’s most memorable work.