Produced by Paul LaRosa, Michelle Feuer and Cassandra Marshall
[This story was originally broadcast on Jan. 7. It was updated on July 14.]
(CBS) SPRINGFIELD, Ga. - On Aug. 25, 2008, hours before dawn, Sheriff Jimmie McDuffie was called to a house on Springfield Egypt Road. He braced himself for what lay ahead.
"I knew then that somebody had been killed, at least two... I did not know who it was. They just gave us an address on a page," Sheriff McDuffie told "48 Hours Mystery" correspondent Susan Spencer. "At some point, and I don't remember where that was at...it was like 'Oh my God, that's gotta be Philip's house.'"
Philip was Philip Heidt - a man to be reckoned with in Effingham County, Ga., and a pal of McDuffie's.
"I knew Philip ever since I came to the county back in probably '87, '88..."the sheriff said.
Heidt was a successful real estate developer who'd made millions in this sprawling county about an hour north of Savannah. The patriarch of a close-knit family, he was married to wife Linda for 42 years.
"We met at the county fair in Savannah...and he stole my heart right away...and um, things weren't always easy but...ya know, there was love," Linda Heidt told Spencer.
The couple had three sons: Craig, Chris and Carey, who Linda describes as, "Good men...fine men...church-going men... They had values and they believed in each other."
Chris Heidt was the middle son.
"We got along well. We were family, nobody was perfect...but we grew up very close together," Chris explained. "Each of us had our own personalities."
"Were the brothers very different?" Spencer asked Carey's wife, Robin Heidt.
"They're all three pretty different, yeah. Chris and Craig are the most alike," she replied. "They both like to hunt, outdoors things like that... And Carey was the baby of the family."
It was Carey who followed his dad into real estate, becoming his business partner. He and wife Robin had three kids of their own.
"Carey and I met in high school our senior year in English class," said Robin.
"You had a big smile when you said that," Spencer commented.
"Yeah, um, we were really good friends in the beginning and realized that I was in love with Carey...and not long after high school we got married."
"When he asked you to marry him, then this just seemed like this was meant to be?"
"It was definitely meant to be, yes," said Robin.
The Heidt clan was turning out just as its patriarch had hoped.
"Philip wanted the family to be perfect... good Christian family, good folks...and Philip was just - he was the man of the house," said McDuffie.
"Popular?" Spencer asked.
"Popular, extremely," the sheriff said.
Murder just didn't fit with the seemingly perfect family the sheriff knew so well... too well for him to oversee the case, he decided. So on that first day, McDuffie turned the case over to the Georgia Bureau of Investigation (GBI).
In charge was Agent Eugene Howard, who quickly realized that the crime scene was not what it seemed.
"The scene was staged to look like it was a burglary," said Agent Howard.
The killer had cut the phones lines and smashed a pane of glass in a door.
"There was nothing of note taken; jewelry was still present. Nothing was rummaged through. There was money left out," Howard explained. "No impression that anything was taken from inside the residence."
"So you think that's just because the person panicked and fled before they had a chance to take anything?" asked Spencer.
"No," Howard replied. "Robbery wasn't the motive. Murder was the motive."
"There were three victims shot, each with a single shotgun blast," Medical Examiner Dr. James Downs explained.
"The shooter comes to Carey first. Fires. ...The shooter leaves Carey, proceeds to the parents' bedroom...the second shot was to Philip. Linda was the mother...she's comin' outta the bathroom to see what's going on because she doesn't have a clue... the left side of her face was extensively damaged and then the shot continued through her right shoulder.
"Both of the men had similar entry wounds -- that is a shotgun wound to the face," Downs said of murder victims Philip and Carey Heidt.
Based on those injuries and the pellets found at the scene, the medical examiner says the shooter used a 12-gauge shotgun; up close and personal.
"How close roughly are we talking about here?" Spencer asked Downs.
"Based on what I've seen at the scene, looking at the photographs, my estimate was something like two feet," he replied. "You're two feet away, my goodness. You don't really need to aim. You just kinda point and shoot."
To get an idea of the damage a 12-gauge shotgun does at such close range, "48 Hours" asked the sheriff's firearms instructor, Ed Myrick, to demonstrate using the same model shotgun, the same type of buckshot and the same three-inch shell used by the killer.
"This is the Remington 870," Myrick explained. "This is their most popular shotgun."
"What would this do if fired at a person?" Spencer asked.
"If you're gonna fire that at someone, it's a deadly force incident," Myrick replied.
Given the close range, Linda probably would have died instantly had she not turned her head at the moment of impact.
"It's amazing that she did survive because, basically, it looks like she was left for dead," said Downs.
But, almost as if the power of those shotgun blasts wasn't enough, the gunman next drenched the entire house in gasoline.
"The gas fumes out by the road were just horrific," McDuffie recalled. "You could smell it from the road."
"I wrote down in my journal that I knew what hell smelled like...Gasoline and gunpowder," Linda told Spencer. "I remember smelling the gas..."
"You had gasoline on your clothes?" asked Spencer.
"Yeah, well, I was sitting on the floor so I knew they were wet."
But the killer never set the gas ablaze, perhaps panicking when he heard Linda's desperate call to 911.
News of the murders spread quickly in this rural southern community and so did fear.
"They must've thought a killer [was] on the loose," said Spencer.
According to McDuffie, "They did."
Investigators checked the alibi of a local drug dealer, but quickly ruled him out. They next turned their attention to the Heidt's real estate dealings.
"Every time Philip had had an argument with somebody, you know, we had to go and investigate and talk to those folks...see what was going on with it," said McDuffie.
They found no motive and no suspect. Then Sheriff McDuffie recalled an unsettling conversation he's had with Carey Heidt only a month earlier.
"...he knew that his wife was runnin' around on him," McDuffie said. "But he did not tell me who it was with."
"That must've been something of a shock," said Spencer.
"It was," the sheriff replied, "'cause every time you saw them together it was just like the perfect family."
As the whole county soon would learn, it was hardly the perfect family. Not only was the marriage on the rocks, but even more shockingly, Robin Heidt was having an affair with her husband's older brother, Craig.
"I'm definitely a woman in the center of a storm," said Robin.