Produced by Sara Ely Hulse and Clare Friedland
[This show originally aired on May 5, 2012]
COLUMBIA, Ill. (CBS) - On the morning of May 5, 2009, Christopher Coleman returned home from the gym to a scene of chaos and unimaginable horror.
"I told him, 'Hey, they -- they didn't make it' -- being the family," Detective Justin Barlow of the Columbia Police Department said. "[Chris] sat down on the driveway and started sobbing. Said he felt like he was gonna throw up. And then kind of curled up in the fetal position."
Detective Barlow had been the Coleman's neighbor for five years and was the first to respond when Chris could not reach his wife.
"This crime scene, it wasn't bloody," he told "48 Hours Mystery" correspondent Maureen Maher. "...but that didn't mean it was less gruesome."
"Were you at all prepared for what you were about to walk into?" Maher asked.
"I don't think anybody could be prepared for that," said Barlow.
Upstairs, where they should have been safe in their beds, were 31-year-old Sheri and the couple's two young boys, 11-year-old Garett, and 9-year-old Gavin.
"What is the lasting image you have in your mind from that day?" Maher asked Barlow.
"I would say the one that sticks out the most would probably be Garett, just because he's the one that -- that, you know, I -- I discovered," he said.
"Is that a haunting image for you?"
"Yeah. Little bit," Barlow nodded.
The killer had not only taken Garett's life, but had desecrated the body by leaving another disturbing message.
"The spray paint in his room was actually on the sheet that was over his body?" asked Maher.
"It was and there was some remnants of the spray paint on him as well," said Barlow.
"We knew that -- that this case was gonna be probably the biggest one -- of our lives -- definitely our careers, probably our lives," said Chief Joe Edwards.
Columbia, Ill., is a small, quiet suburb outside of St. Louis. Chief Edwards calls it "a wonderful place to live and raise a family."
Chief Edwards immediately recognized that his two investigators were going to need some help and called in a special unit - Major Jeff Connor and the Major Case Squad of Greater St. Louis, which brought in an army of 25 seasoned cops.
"It's typically your smaller departments that need the resource -- need the help," Maj. Connor explained.
Hours after the murders, the Major Case Squad swung into high gear. The CSI team started processing the house, warrants were secured to go through the Coleman's phones and computers, while a very distraught Chris was taken to the police station to give his statement.
Coleman told investigators that it had been a normal morning. He got up and left for the gym around 5:40 a.m. and called Sheri numerous times to wake her up.
As neighbors woke to the news of the murders, they were both devastated and terrified.
"So as I got down the street, I see that it was at the Coleman house. And I text her right away and said, 'Is everything OK?' And I didn't get a response," said an emotional Vanessa Riegerix.
Riegerix, who lived down the street, said the Colemans appeared to have a perfect life raising their two beautiful sons.
"I always thought of them as the American family, the perfect family," Riegerix said. "...everybody would want their children like these two boys, polite-- always helpful ...they had a heart of gold."
The couple had been married for 12 years and met when they were both in the military, training at the K9 unit. Sheri became a stay-at-home mom.
Chris, 32, the son of a preacher, used his Marine and security experience to land a job for a well-known televangelist, Joyce Meyer.
"Joyce Meyer is now known throughout the country, and known throughout the world -- as a leading voice in the evangelical movement," St Louis Post-Dispatch reporter Nick Pistor explained. "She's extremely successful financially. ...I've seen figures from $50 million to $100 million a year."
Pistor has followed the Coleman case for the last three years and is a CBS News consultant.
"Joyce Meyer does conferences all throughout the world in countries that have -- that don't necessarily respond well -- to women who -- are preaching -- a Christian message. And so she wanted some deeper security," he said.
But being Joyce Meyer's head of security apparently put a target on Chris Coleman's back. In November 2008, Chris had begun receiving death threats to his work email.
"Whenever Chris Coleman reported the first death threat that he got from his e-mail account at w-- at his work at Joyce Meyer Ministries, he came to us at the police department," said Barlow.
The email read:
Tell Joyce to stop preaching the bull---- if I can't get to Joyce, then I will get to someone close to her
"We give the Coleman family... extra patrol which we just patrol the area a lot more than we normally would during a shift and give it special attention to make sure nobody's there," explained Barlow.
It was in January 2009, that a hand-delivered threat showed up in the mailbox at the Coleman family home. It read:
F--- You! Deny your God publically or else. No more oppurtunities [sic]. Time is running out for you and your family!
"Did it concern you as a neighbor living so closely when you heard that there were death treats being made to the guy who lived across the street?" Maher asked Barlow.
"Absolutely," he replied.
Each note seemed to escalate the seriousness of the situation and, on April 27, less than a week before the murders, a final missive arrived with an ultimatum:
Stop today or else. I know your schedule! You can't hide from me forever. I'm always watching. I know when you leave in the morning and I know when you stay home.
"You decided to ramp things up yourself to be proactive," Maher noted to Barlow. "And what did you do at your house?"
"We got one camera mounted up in my 5-year-old's bedroom and pointed it right at the mailbox," he replied.
With the camera aimed directly at the Coleman's mailbox, about 214 feet away approximately, according to Barlow, they hoped to get a clear shot of whoever was leaving the notes.
"...and be prepared for something that was gonna happen. And be as proactive about it as we could," said Barlow.
Instead, days later, the killer somehow snuck into the Coleman home and strangled Sheri, Garett and Gavin.
But if the murders were linked to the threats and Joyce Meyer Ministries, that meant the cops might now be on a global search for suspects.
"There was a lot of fear that there was somebody out there killin' families, and who was gonna be next?" said Maj. Connor.