On a chilly Sunday in Northern Arkansas in February 2008, Det. Alan Roberson of the Cumberland County Police received a call about an accident at an isolated vacation spot called the Little Red River.
"There had been a report that a gentleman -- Matthew Sheppard -- had fallen off the dock into the river and had disappeared," Roberson said.
The call was placed by Monica Sheppard, the Mexican-born wife of Matthew Sheppard, 42. The two had gone to the river for a weekend getaway with their 7-year-old daughter, Chariss.
On the day of the accident, Sheppard said, she and her husband took a walk outside their cabin with their black labrador, Fluke. But just as they reached the end of the dock, their peaceful weekend came to a sudden end.
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Fluke fell into the water and, Sheppard said, her husband reached over the dock, attempting to grab the dog's collar. Then he lost his footing and fell into the water himself.
He was able to push the dog to safety but quickly found himself overtaken by the river's strong current, his wife reported.
"At first I thought he was playing with me, trying to scare me, and I said, 'Come on, get out of there,' and he said he couldn't breathe," Sheppard said. "Then he went down and I didn't see him again. So I just ran to the cabin and grabbed my phone and called 911."
When police arrived at the scene, they were immediately concerned by the conditions they found. The freezing river was 12 to 15 feet deep where Sheppard reportedly fell in. Jagged timbers and logs lurked under the surface.
Word of the accident soon spread. Residents of Searcy, Ark., the small town where the Sheppards lived, mobilized to join the search effort as soon as they heard of the disappearance.
"We had sonar, we had underwater cameras, we had at the peak probably 60, 70 people searching for Matthew Sheppard," Cumberland County Sherriff Marty Moss said.
Even if Sheppard had perished in the river, searchers were expecting to recover his body.
"From the dive teams, people who have dealt with those situations, they say you'll usually find the body within 40 to 50 feet," detective Roberson said. "It will go directly to the bottom at first."
The water flow at a huge dam several miles upriver was completely stopped for the first time in years so the river could be made shallower and the search easier. And then, late in the day after Sheppard disappeared, searchers made what seemed like a breakthrough.
A hat, which Monica Sheppard told the police her husband was wearing when he went into the water, was found 30 yards downstream from the dock.
Searchers now believed it was only a matter of time before Sheppard's body was recovered from the river.
But even if they had recovered it, Monica Sheppard would not have been there to see it. In a move that roused suspicion in Roberson, she left the river the morning after her husband's disappearance.
"Usually, the relatives seem to want to stay," he said. "You can't make them leave. They just refuse to go, but she, around 9:30 or 10, went home."