Nov. 12, 2010 -- When Candy, a second-grade teacher, was approached by a man named Jovan Collier on a sunny Florida beach, it seemed like the beginning of her happily-ever-after.
"It was a whirlwind," Candy said. "We hit it off that day. ... It was really quick. He was very charming, [a] smooth talker, sweet, you know, funny."
Candy and Collier quickly learned that they shared more than good looks. Both recently had moved to the St. Petersburg area and were trying to build a new life.
"I was looking for someone to share my life with," Candy told 20/20's co-anchor Chris Cuomo. "I was just missing a significant other that I really wanted."
They also both had coped with loss.
"I'd been through a lot of tough times, lots of deaths in my family," Candy said. "That first day at the beach, he told me that his parents had been killed in a tragic car accident by drunk drivers. He had always felt like he was missing something."
Candy knew immediately that Collier was missing a happy childhood. What she didn't know was that the man sharing her bed also may have been missing a conscience and that her romance soon would morph into a real-life horror story.
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While Collier was attractive, intelligent and ambitious, this apparent total package came with a fuzzy web of connections. He would regularly leave Florida for the Midwest to visit friends, an ex-wife and his son. Candy later found out that Collier also was reconnecting with a daughter named Nicole from whose life he had been conspicuously absent for nearly six years.
Luckily for Collier, Candy was supportive.
"I do care about his daughter," Candy said. "[She's] a very nice young lady."
These feelings worked both ways.
"It was very neat to see that," Nicole said. "I mean, my dad was getting his life back on track, settling down, hopefully for good."
As Collier learned again to be a father, he was given the chance to be a son. It turned out that the parents who, according to Collier, had died in a car crash were actually adoptive parents to whom he was given at birth.
"I honestly had abandonment issues my entire life," Collier told "20/20." "I never felt like I was part of anything. I was reminded that I was adopted a lot. I was told that my mother was a whore. You know: 'She's a horrible person, trailer trash,' and blah, blah, blah."
But his birth mother was far from "trailer trash."
She is, in fact, an attractive Atlanta realtor married to an affluent plastic surgeon. And after searching for years, she was able to track down her long-lost son.
For a while, everything was working out.
"[His relatives] were lovely people," Candy said. "We got along fine. We had good times. We spent Thanksgiving together. ... Everything seemed fine."
But in the summer of 2008, Jovan informed Candy he was no longer speaking to his mother. He said it was because she'd badmouthed Candy, allegedly saying that Collier was too good for her. But that was a lie.
In truth, Collier's mother had disinterred the deep secret of murders committed 25 years earlier by a troubled, adopted 14-year-old boy named Peter Zimmer.
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Grisly Triple Murder Rocked Rural Wisconsin
More than 1,000 miles away from St. Petersburg, amid the fields and farmhouses of southwestern Wisconsin, sits a speck on the map named Mineral Point, a slice of Americana locally known for crystal mining and Cornish pasties.
On May 23, 1983, acting on a tip, sheriff's deputies drove to the Zimmer home on an isolated country road. They found the most grisly scene they'd ever seen.
"I have been involved in well over 100 homicide investigations," said one of the first responders, Bob Hille, an Iowa County deputy sheriff, "and this is the only case that I ever have [had] bad dreams about."
On the back porch, deputies found the father, Hans Zimmer, shot five times. The mother, Sally Zimmer, had been stabbed to death and carried into a shed behind the house with a rosary cast upon her body.
"The knife went through the thickest part of the skull above the ear and completely penetrated the skull," Hille said.
Those horrors, however, were not the worst of it. Most disturbingly, the body of one of the couple's adopted sons, 11-year-old Perry, was discovered upstairs. Perry had been stabbed more than 25 times and was covered in defensive wounds.
"This little boy really bothered me," Hille said. "He put up such a fight to try and save his life, to no avail."
It quickly became apparent that the culprit behind the heinous crimes was Peter Zimmer, Perry's 14-year-old brother.
"One car was gone," Hille said. "One member of the family was gone. ... He was nowhere to be found ... and just became immediately the suspect to look for."
It didn't take long to apprehend Peter. It also didn't take much time for the boy who was a killer to become a free man.
Despite the heinous nature of his crimes, Wisconsin law at the time only allowed that Peter be prosecuted as a juvenile.
He pleaded no contest to the killings and served just more than a year for each murder -- not in the state penitentiary, but at the Ethan Allen School for Boys.
Records show that during his time there, Peter did not seek to get psychiatric help, but to get rich. He declared that he planned to claim his family's estate as the sole surviving heir.
Again, the law fell in his favor. So in 1987, he walked out of Ethan Allen a free man with a clean record, a trust fund and, soon, a new name: Jovan Collier.
Name Name, New Beginning for Jovan Collier
During his time at Ethan Allen, Peter made a connection with a 19-year-old counseling volunteer who said he started opening up to her about his nightmares.
"[Nightmares] about the killings -- he said he'd have nightmares every single night and wake up screaming and crying," said the volunteer, Belinda. "He said he was abused."
After Peter was released and became Jovan Collier, his relationship with Belinda grew to something more.
"I was really comfortable with him; he was really comfortable with me," she said. "And he was charming. ... I was like his princess."
Belinda was not discouraged by his dark past.
"I didn't think about it that much," she said. "I mean, I concentrated on who he was now. I believe in second chances."
Shortly after the couple started a life together, they had a daughter -- Nicole -- who grew up oblivious to the crimes of her father.
"It's not something that I ever was prepared for," she told "20/20." "When I found out about his past, I wasn't sure at all how to feel. I wasn't sure if I should be mad at him or scared of him. I had no idea how I should be with him."
Up until the summer of 2008, Collier's birth mother was equally oblivious to her son's past. But her family soon grew suspicious enough to hire a private investigator, Robin Martinelli, to dig into his history.
"There was just something different about him," Martinelli said, "that the birth mother's husband thought there needed to be some background checked out."
When Martinelli learned the truth, Collier's birth mother abandoned him again.
'I Was Living a Nightmare'
Unaware of his past, Candy continued to date Collier. That relationship eventually collapsed in 2009, when Candy found Collier's profile on a racy dating site.
"I made him move out," she said. "He moved out. I called it off."
That end was only the beginning of her own personal hell.
"It was a nightmare," she said. "I was living a nightmare."
As soon as Candy moved Collier out of her home, he inundated her e-mail inbox. The e-mails numbered in the hundreds.
At first, the mass of e-mails was composed of loving, if obsessive, statements: "You are the love of my life and I have been so happy to have found you," he wrote. "Please see how this is really a big misunderstanding."
In a statement to "20/20," Collier claimed it was harmless.
"It's that 'Boy finds love, boy loses love, boy goes on a bender down depression' road," he said.
Teen Killer Turned Stalker
Subsequent e-mails, however, made it difficult to understand how his sentiments could be misunderstood.
"I hope your world caves in," he wrote. "I hope all your pets die. I hope the house falls down while you are in it. I hope you get into a physically altering car crash."
A later e-mail added, "I am here in St. Pete and hope to hell I run into you. You messed me over and I will pay you back. Your job, your rep, all of it."
"I was sending crazy e-mails," Collier said. "I don't remember half of those things. I was washing down ... pills with Stoli every morning. Bad idea."
Candy took out a restraining order against Collier after he threatened her with a knife in public. The piece of paper, however, did little to assuage her fears.
"I would sleep two, three hours a night," she said. "I would be sitting on the couch watching doors."
Despite the volume of e-mails, Candy managed not to miss one that said that Collier had hanged himself in an Orlando hotel.
"I just thought, if anyone's going to know if this is true, his birth mother will know," Candy said. "I called and Joe's stepdad answered the phone. ... He's like, 'Well, you know about the murders, don't you?' I was like, 'I have no idea what you're talking about.' And right then, I just could feel like all the blood just, like, drained from me."
Candy had just learned Collier's dark secret and now he was spiraling out of control.
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