For Jeff Mudgett, one day in early May was a moment of truth, or at least the next step in his pursuit of the truth. Years of research and debate were coming down to this day in a Yeadon, Pennsylvania, cemetery.

“It was straight out of Alfred Hitchcock. It was scary,” Mudgett said.

Anthropologists and archaeologists from the University of Pennsylvania were excavating the gravesite of Mudgett’s great-great grandfather Herman Webster Mudgett, more infamously known as serial killer and con-man H.H. Holmes.

“He’s evil personified! And I decided rather than running away from it, I decided to try to make something worthwhile of coming up with the truth,” Mudgett said.

Some credit Holmes with killing more than two hundred people in the late 1800’s. Most of the killings are believed to have taken place in a building Holmes owned in Chicago, dubbed the “Murder Castle,” events described in the 2003 bestseller "The Devil in the White City." But Holmes was only convicted of one murder. In 1895 he was put on trial in Philadelphia for the murder of his business partner Benjamin Pitezel and was sentenced to die by hanging.

This is where Mudgett and others say the mystery begins.

According to newspaper accounts, Holmes was marched to the gallows at Moyamensing Prison where he was hanged. The prison was located on 1400 South 10th Street in Philadelphia before it closed in 1963 and was demolished in 1968. Holmes’ body was eventually interred at Holy Cross Cemetery in Yeadon. Holmes requested his casket be encased in concrete so no one would steal his body. However, an 1898 newspaper article sparked the conspiracy theory that Holmes somehow escaped death at Moyamensing and ended up in South America.

Fast-forward to 2017 with Mudgett standing in what many believe to be the grave of his murderous relative. Descendants of Holmes were granted permission by a Delaware County judge to exhume the remains.

“It actually brought tears to my eyes,” Mudgett said. “And I was sitting there, trying to figure out, ‘why am I crying for this monster of a man?’”

As they dug, the group found a wooden box.

“We dug down to 10 feet and we found a fake pine box,” Mudgett said.

Mudgett told the NBC10 Investigators there was nothing in the box and he was ready to give up but the team continued to dig. Next, they ran into the cement reported on in 1890s newspaper accounts.

"And we found the cement sarcophagus, which many of the newspapers described back then. That’s when the hard work began,” Mudgett said.

After breaking through the cement, the team from Penn found what they were looking for.

“They carefully opened it up and we found a skeleton of a man, which we removed and took to the university,” Mudgett said.

Before the remains were taken away, Mudgett held the skull in his hand.

"To see that skeleton and that skull with the brains still inside, which is a phenomenon that the scientists still haven’t explained, scared the heck out of me," Mudgett said.

Once the remains were taking to Penn, the tests began to see if the bones belonged to Holmes.

“We were there when they took the DNA samples from the skull and, you know, put them in the proper packaging. They took some comparison DNA from me,” Mudgett said.

But Mudgett’s crusade to see if Holmes was actually buried in the grave has another angle.

"Here was a moment that could possibly change American and English history. And it was staring us in the face," he said.

Mudgett believes his great-great grandfather is not only H.H. Holmes but also Jack the Ripper.

"As of yet, I still haven’t seen anything which would cause me to change my mind regarding my theories that H.H. Holmes was Jack the Ripper," he said.

While there is skepticism among Holmes experts about the Jack the Ripper theory, it is another reason Mudgett and his team spent time searching for and finding the tomb where Holmes was believed to be buried.

The great-great grandson is currently starring in a History Channel show entitled “American Ripper.” The premise of the show has Mudgett connecting the two notorious killers as the same man.

“Jack the Ripper was the J-V compared to H.H. Holmes. In my opinion, the world should be trying to prove Jack the Ripper was H.H. Holmes, not me proving Holmes was Jack the Ripper,” Mudgett said.

The last piece of the puzzle seems to be the DNA taken from the found remains and Mudgett. Those results are not yet in.

"I have my beliefs, I have, you know, doubts. I want to see those DNA results to come up with a firm conclusion," he said. "I’m waiting for them right now. I could get a phone call as we speak, right now."

As for the remains, a lawyer for Holmes’ descendants told a judge they are still at Penn awaiting more testing. He believed they could be returned to Holy Cross Cemetery in late July.

