This is the conclusion to a KHQA Special Report, Marvin the Mummy: Revisited. You can view the first part of the report here .
Thousands of hours of investigation, dozens of leads, and zero answers as to who killed Marvin the Mummy.
Investigators were no closer to solving the mystery than they were the day the body was found in April of 1985.
Until one day in 2008.
A break in the case
For Adams County State's Attorney Jon Barnard, it was just another day at work.
Then the phone rang.
"I was sitting at my desk here, minding my own business and I get a phone call from sheriff's department investigators in Mississippi," Barnard said.
Authorities in Alcorn County, Mississippi were calling Barnard about a man they had in custody on a forgery charge.
But as it turns out, this man liked to talk.
He brought up the body in the abandoned rock quarry, talked about how the man was killed, and eventually, described the signature piece of evidence in the case.
"He proceeded to describe this tattoo to a tee," Barnard said of the tattoo found on the victim's right forearm. "He provided details that left no question whatsoever, but that he was the one who killed Marvin the Mummy."
Investigators knew the tattoo of a Grim Reaper-style skeleton firing a shotgun was unique; there was no way to accurately describe it unless you had seen it before.
This was what they had waited for.
The man with the answers
The man behind those details was Wallace Spence, a 40-something man with a history of criminal activity.
Here's what he told investigators.
Spence and the victim were driving through the southeast on a petty crime spree.
At some point along the way, the victim made an unwanted sexual advance towards Spence.
In a fit of rage, Spence struck the victim in the chest with a lead-filled baseball bat and drove off.
However, Spence saw the man stumble to his feet in the rearview mirror.
At that point, Spence turned around and ran over the victim with his car - twice.
"(He) struck him full-on at about 40 miles-an-hour, and according to Spence, he knocked him right out of his shoes," Barnard said.
He then put the victim in the trunk and drove over 400 miles to the rock quarry in northwest Adams County before dumping the body.
Spence's story added up; investigators had their suspect.
The other mystery man
Though a suspect had come forward, the most puzzling question of the case still wasn't answered.
Who was Marvin the Mummy, and why weren't authorities able to identify him for so long?
Larry Hood was the lead crime scene analyst of the Marvin case.
Even with a complete set of fingerprints from the victim, an identity was never found.
But everything cleared up once Spence confessed.
"(Mississippi authorities) contacted the Florida Department of Corrections and sure enough, our victim had been in prison. He had been fingerprinted, but his file had somehow slipped through the cracks and had not been entered into the system," Hood said.
That's right - it was a procedural error that left the mummy unidentified for 23 years.
Nearly a quarter-century after the body was first found, investigators learned the name of the man in the quarry: Thomas Brannon.
Brannon and Spence knew each other from serving prison time together in Florida.
It's important to note, as Hood pointed out during his interview, that the body was found before modern DNA technology was available.
Matching a victim to an identity based on today's methods simply was not possible at the time.
Mike Ernst was the Illinois State Police case agent for Marvin the Mummy.
He said the confession was the only piece investigators had been missing for 23 years.
"Neither (Spence nor Brannon) had any connection to the Quincy area, and there was really no way we could have ever solved the case without him confessing," Ernst said.
After all those years, investigators finally found closure.
"Closure was huge, particularly for law enforcement here in Adams County that I can speak for because they worked so hard on it," Barnard said.
"I felt good because I did my job," Larry Hood added. "I defy anyone to criticize my work on this case because it was right, and right on the money."
For those wondering, authorities had no way to charge Spence with murder in the State of Illinois as there was no evidence to support or refute Spence's confession that the murder happened in Kentucky.
Everything authorities had in 2008 was based on one person's re-telling of the events.
As a result, Spence was charged in Illinois with concealing a homicidal death and sentenced to eight years in the Illinois Department of Corrections.
While serving his sentence, authorities escorted Spence to Kentucky where he was able to point out the likely spot in Edmonson County where he committed the murder.
He was then charged with murder in Kentucky and sentenced to 12 years in the Kentucky Department of Corrections.
It is unclear just how much time Spence actually served for murdering Brannon, but both Barnard and Hood confirmed that Spence was released well before his sentence expired.
He was arrested again in January of this year on a burglary charge and sentenced to one year in a Kentucky prison.
That sentence expires in January 2015, but Spence is eligible for release as early as next month.
Why has this case re-surfaced?
It might seem odd to revisit the case six years after it was solved; why open it back up?
Because it's about to get the spotlight from a national TV network.
Earlier this summer, Jon Barnard, Larry Hood, and Mike Ernst received a call from a television producer with the Investigation Discovery (ID) network in Los Angeles.
She had come across the story of Marvin the Mummy and wanted to hear from those involved.
It wasn't long after that a crew from the network traveled to Quincy to interview several investigators and visit the site where Thomas Brannon was found.
It's all going to be featured on a new show called 'Murder Book', and an entire episode will be dedicated to Marvin the Mummy.
An exact air date has not yet been announced, but the show is currently in production and will air sometime next year.
KHQA will bring you those details as soon as they become available.
More to the story
Now to unveil two details that were left out of the TV segment due to time constraints.
First, there is some debate as to how long Brannon's body went undiscovered.
Larry Hood told KHQA he believed Brannon was killed on January 20, 1985, the day of Super Bowl XIX.
However, other sources indicate Brannon might have been killed sometime in late summer of 1984.
Second, after the murder, Wallace Spence assumed the identity of Thomas Brannon. He even married and had kids under the false name.
This might lead you to question Spence's motive and confession, but there is no evidence to support anything other than what Spence told authorities in 2008.
There is also debate as to whether Spence acted in alone in hiding the body - did he really find that secluded rock quarry on his own?
Again, it's only speculation.
But there is one more question that will probably never be answered: why did he decide to confess after 23 years when he could have just as easily said nothing and avoided a prison sentence?
Those are details, just like the ones surrounding Thomas Brannon's murder, that only Wallace Spence knows.