Watching home videos of his family brings an instant smile to Mark Unger's face.
"It was love at first sight with Flo," said Unger. "She was my other half."
"Flo" was Florence, Mark Unger's wife of 13 years. She was an amateur photographer, who loved taking pictures of their children, Tyler and Max.
The family lived in an upscale Detroit suburb, but one of their favorite escapes was a peaceful lakeside resort called Watervale. It was there that 37-year-old Flo Unger lost her life.
Her husband was the only suspect, and in May 2004 Mark Unger was arrested and pleaded not guilty to the murder of his wife.
When Glenn Stark -- one of Mark Unger's closest friends -- reluctantly came forward, he admitted to having a secret two-year affair with Florence. He said he had sex with her days before she died. According to prosecutors, that affair was a possible motive.
But the defense challenged the prosecution, saying police work was shoddy and evidence nil. The crux of their defense was computer animations that created dramatic visual evidence of how Florence Unger may have fallen instead of being pushed. But was it enough?
On Oct. 24, 2003, the Unger family were making the familiar four-hour drive from their home to Watervale.
But this wasn't like other family trips -- the Ungers had hit a patch of rough times.
Mark had become an alcoholic and gambled away thousands of dollars at casinos. He'd spent five months in rehab and decided that instead of going back to his job as a mortgage broker, he'd stay home and take care of the kids.
Friends say Flo was fed up and resented that she had to get a job; they said she had even started divorce proceedings.
Friends also said that Mark wanted to stay together and had convinced Flo the weekend away would be good for the family.
The Ungers were staying at a cottage called the "Mary Ellen" -- just a few hundred yards from the lake with its boat deck. It was a favorite spot for guests of the resort to have a glass of wine and watch evening sunsets.
On that October evening, Mark and Flo were outside talking on the deck. Soon after, Mark says Flo asked him to check on the boys, and he left her outside, alone in the dark.
Mark says he put the boys to bed and when he came back out -- more than an hour later -- his wife wasn't there.
Thinking his wife had gone to visit friends at another cottage, Mark said that he went inside to watch a DVD and fell asleep. When he awoke at about 7:30 in the morning, Mark said he realized Flo had never come home.
Mark said he called the friends -- Linn Duncan and his wife, Maggie, who own the resort -- in a panic, telling them Flo was missing.
They spread out to search, and the Duncans were the first to spot Flo Unger, lying face down in the cold shallow water.
"I looked down there I could see her in the water," said Linn Duncan. "And, I just, after a minute or so I started to cry. … My first reaction was suicide."
Linn walked up the hill and broke the news with four simple, devastating words.
"I said, 'She's in the water.' And he ran right to it. Right to the spot," Linn said.
The Duncans called 911, and Deputy Sheriff Troy Packard was first on the scene.
"I noticed that the top railing was broken, fractured out," Packard said. "Next I noticed a rather large pool of blood."