Part I of a Telegraph exclusive. Read Part II: 'Unmissable' in Monday's Telegraph.

David S. Vandiver, an athletic man in his late 40s, spent the last Sunday in June in Southern California honing his golf game at an instructional school near Palm Springs.

He remembers because, nearly six months later, he remembers most everything about that trip in excruciating detail.

He was in a rental car that Sunday evening, on his way to the airport. At a stoplight, he scrolled through his iPhone’s e-mail inbox. He noticed a message from his girlfriend, Lauren Giddings, back home in Georgia. She’d sent the message the night before. Vandiver glanced at the first line or so but no more.

“I just had an awkward conversation,” her message began.

Giddings wrote that a friend of hers had inquired about her romance with Vandiver. It wasn’t something Vandiver cared to get into from 1,900 miles away by e-mail or by phone. He did not read the rest of the message and didn’t reply. “I put it off,” he says, and he drove on.

“I’m like, ‘Wow, why is this particular person jumping into what I presume to be probing questions about where Lauren and I were going relationship-wise?’” Vandiver, 48, recalls. “It’s just not that person’s business. That’s just the way I thought of it, and that’s why I put the phone down.”

He was flying home to Atlanta that night. He told himself, “I know she’ll bring it up again and we’ll talk.”

But they didn’t. Nor would they.

A few days passed. Vandiver didn’t hear from her. That was not unusual. They weren’t ones to be in touch every day. Giddings, who’d graduated law school the month before, was cramming for the Georgia bar exam. She was days from vacating her downtown Macon apartment, about to move in with Vandiver in Atlanta.

It was not until Wednesday evening, four nights after Giddings’ e-mail to him, that Vandiver realized there had been more to her message, other subjects.

Vandiver, on his way home from dinner, got a call from Giddings’ brother-in-law, Dan Wheeler, in Maryland, where Giddings had grown up and where her family still lives. Vandiver was alarmed to learn that no one close to Giddings had seen or heard from her since the weekend.

He looked at his phone, pulled up the Saturday night e-mail sent from Giddings’ Google account and read her words again. This time all the way through.

“I was completely wrong,” he says, “about what it was about.”

There in the waning hours of June 29 it became increasingly apparent that Lauren Teresa Giddings, the woman who’d won his heart, had vanished, and that he had been the last person she reached out to.

* * *

Vandiver won’t share the full text of the message Giddings sent him at 10:13 p.m. Eastern time on June 25, four-and-a-half days before her dismembered torso turned up in a garbage can outside her Georgia Avenue apartment.

“I know,” he says of the message, “that that’s likely to be a focal point at the trial.”

However, in several conversations with The Telegraph since early November, he revealed some of that e-mail’s contents and talked candidly about his nearly four-year relationship with Giddings.

Vandiver also spoke openly of the emotional toll the grim details of Giddings’ slaying have taken on him, as well as of his cooperation with the police and the measures he took to clear his name of any involvement in her death.

He also offered his thoughts on the man charged with killing the 27-year-old Giddings and of how she had on occasion described that man, her next-door neighbor and Mercer University law school graduating classmate, as an anti-social creep.

Stephen Mark McDaniel, who turned 26 in September, was interrogated and jailed on burglary charges -- charges unrelated to Giddings’ death -- within 18 hours of the June 30 discovery of her body. McDaniel was charged with her murder Aug. 2.

McDaniel’s mother and his lawyer have professed his innocence.

* * *

Vandiver says that final e-mail from Giddings covered a range of topics. Their relationship. Her pending moving plans. She also mentioned an apparent break-in try at her apartment by local “hoodlums” a couple of nights earlier.

Giddings also noted that she’d hoped the next tenant moving into her apartment would buy some of her furniture. But it turned out the tenant was allergic to dogs. Giddings’ sidekick Butterbean, a Pekingese-poodle mix, had lived with her during most of her time in Macon.

Though there may be no way to know for sure, Vandiver thinks Giddings at least started writing the e-mail he received. The writing matched her style. Details in it were things only she could know.

But one curious aspect of the case has been the message’s use of the word “hoodlums.”

McDaniel, when interviewed by reporters the day Giddings’ torso was found, mentioned the e-mail and some of what was in it -- the line that included “hoodlums.”

Late the previous night, he and Giddings’ friends apparently read the message on her computer when her friends, concerned because they hadn’t seen or heard from Giddings in a few days, went to her apartment to look for her.

“That’s what she said in the e-mail,” McDaniel told reporters. “She thought that someone had tried to break into her apartment. She said it, like, ‘Macon hoodlums tried to break into my apartment on Thursday night.’ ”

Might the line have been typed by a killer trying to throw off the cops? Or was Giddings the author, merely mentioning it in passing in her e-mail?

Answers might never emerge.

Vandiver has entertained the possibility that someone besides Lauren might have finished the message, added to it or taken something out and then sent it.

“Was there a knock on the door while she was writing that, she didn’t get to finish and somebody hit send? McDaniel? I mean, I don’t know,” Vandiver says. “But I do think she at least started that e-mail.”

* * *

In the days leading up to the Fourth of July, police let Giddings’ family go into her apartment and pack her things.

Police stood by, ready to make note of or examine anything unusual that her family might find.

A diamond necklace, a gift Vandiver gave Giddings for her 26th birthday in April 2010, is still unaccounted for.

So is a silver-and-gold, intertwining rope bracelet he gave her for Christmas last year.

“I have no idea what has become of them,” Vandiver says.

Authorities have never publicly mentioned the jewelry.

Vandiver, who believes McDaniel is the person who killed Giddings, thinks it’s possible that the items could be with the rest of Giddings’ remains, wherever they might be.

Or, Vandiver says, stashed somewhere as a “sick keepsake” by her killer.

“Or the police could have it as evidence,” he adds. “Maybe that was also found in his apartment. I don’t know.”

* * *

Vandiver says that on his infrequent trips to Macon to visit Giddings at her Georgia Avenue apartment, he never saw her neighbor McDaniel.

The first time Vandiver laid eyes on him was at McDaniel’s late-August commitment hearing in the Bibb County Courthouse.

Vandiver’s first impressions of the murder suspect? “That he was evil and the lowest form of a coward. ... The personification of evil. ... He’s a depraved, black-hearted person.”

Vandiver says McDaniel wasn’t a person Giddings talked about often, but she had mentioned him.

“She called him creepy and weird,” Vandiver recalls, adding that Giddings also described McDaniel as an “anti-social recluse.”

Though Giddings was outgoing and friendly, Vandiver says she had no “friendship” with McDaniel.

“She treated him with probably more respect than it sounds like he ever got in his life,” Vandiver says. “I know that she had no desire to socialize with him.”

When Giddings told Vandiver she’d been elected president of Mercer’s Federalist Society, she also informed him of McDaniel’s successful bid to be second in charge, telling Vandiver, “But my creepy neighbor got elected vice president.”

In another e-mail, Vandiver says, she recounted how McDaniel had ordered pork for a Federalist Society meeting when he had to have known there were Muslims in the group who would attend.

In a September 2008 e-mail that Giddings sent to Vandiver, she referred to her neighbor McDaniel again.

This time after a class that she and McDaniel had together.

Giddings wrote that she’d contradicted “the crazy guy next door in torts and got the stink-eye; he’s out to get me.”

* * *

Vandiver last saw Giddings at his house in Atlanta on the Wednesday before she vanished.

She was on her way to Macon, driving back from her sister Kaitlyn’s wedding in Maryland. Vandiver had also attended the nuptials, but he flew home.

She stopped in Atlanta and spent the night at his place on Tuesday.

Her plans were to go to Macon the next day to study for the bar, get ready to pack and have something of a “last fling” with her friends, Vandiver says.

When Wednesday morning came, Vandiver headed to work “in a hurry, which I regret.”

Their last words to one another, Vandiver says, were small talk, chitchat.

“I didn’t think it would be any time at all until I would see her again,” he says.

A week later, on June 29, Vandiver was riding home from dinner with a friend. Vandiver’s cell phone rang. The call was from an area code he didn’t recognize. He didn’t answer it.

The caller had been Giddings’ new brother-in-law, Dan Wheeler.

Wheeler called a second time. Vandiver answered. Wheeler asked when he’d last seen Giddings.

No one had heard from Giddings since June 25, which was unusual because she was in touch with family most every day.

Wheeler’s call, Vandiver says, “raised some concern, ... some alarm bells.”

Later that night, some of Giddings’ friends called him.

Vandiver, meanwhile, sent Giddings a text message asking where she was.

Some of the couple’s friends in Atlanta drove to Macon late that night to help friends in Macon look for Lauren.

When the friends from Atlanta arrived about midnight, McDaniel, Giddings’ next-door neighbor, was there helping the Macon group search.

Vandiver says it “sure seems unusual and suspicious that he would pick that occasion to jump out and become and, I guess, not be anti-social.”

Vandiver stayed home awaiting news.

After sleeping for about an hour between 5 and 6 a.m., he called for an update on the search in Macon. Giddings hadn’t turned up.

Vandiver went to his office, knowing that many of her friends would be at the Atlanta law firm where he works. She’d interned there in 2007 and gotten to know a number of his colleagues.

It would be a “convenient place to get more information,” Vandiver recalls. “The people that know and love her were there, at work.”

Later that morning, he and three friends who were also friends of Giddings’ drove to Macon.

It was just after 10.

“I was still holding onto hope that it wasn’t anything bad, or what it appeared to be,” Vandiver says.

* * *

As they closed in on Macon, it was after 11.

Kristin Miller, one of Giddings’ best friends from their years as undergraduates at Agnes Scott College, was in the car. Along with her she’d brought missing-person fliers with Giddings’ picture on them.

Miller got a phone call.

“A body had been discovered,” Vandiver says.

Word was that the body had been found at an apartment complex where Giddings lived directly across the street from the law school.

“It seemed pretty obvious, unfortunately,” Vandiver says.

Vandiver and Miller and the two friends who’d traveled with them went to the police station. An officer was about to show them to a back room, but when the officer learned the group wasn’t from Giddings’ family, the four were asked to wait outside.

It was lunchtime, so the four friends went to a downtown restaurant. Vandiver and Miller didn’t eat. Vandiver says he couldn’t.

Then he got a phone call he’d been expecting. The police wanted to talk to him.

“I fully understood that,” he says.

* * *

Being questioned by police about his girlfriend’s disappearance was a surreal experience for Vandiver.

“It really seemed like a horrific dream. ... You try to convince yourself that it wasn’t happening, that it didn’t happen, but it just kept going on and on,” he says, “and it was very clearly real.”

He wrote a four-page statement before police interviewed him.

Later, he gave police receipts from his trip to California and told them how to access time-stamped, online golf training videos of him from the trip.

“I said I’d give them anything they needed,” he says.

During the interview, a detective wanted to know why Vandiver hadn’t driven to Macon in his car instead of catching a ride with friends. Vandiver says it was because his friends “didn’t think I was in any condition to drive.”

He understood why the question was asked. Police were casting a wide net.

“But to hear these questions coming at you, it still hurts,” Vandiver says. “You know the truth, but you see somebody get potentially suspicious about something you know you had nothing to do with, it definitely hurts.”

Police also asked him, “Who would harm Lauren?”

At no point during the six hours of questioning did they tell Vandiver what had happened to his girlfriend.

Afterward, detective David Patterson spoke with Vandiver privately.

Vandiver knew going into the interview that a member of Giddings’ family from north Georgia was on his way to identify her body. There’d been plenty of time for the family member to get there.

Vandiver couldn’t understand why police were not telling him if the body was Giddings or someone else, why police seemed to be considering her a missing person.

Vandiver says Patterson asked him if he planned to stay in town and look for Giddings.

“I’m happy to,” Vandiver recalls telling the detective. “I want to. ... But I can’t get beyond what you’re telling me ... that you’ve got one body and you’re still going to fill out a missing persons report.”

It didn’t make sense why the police had yet to identify the body.

It was a few days before Vandiver learned the worst.

The woman he’d hoped to marry was gone.

To contact reporter Amy Leigh Womack, call 744-4398. To contact reporter Joe Kovac Jr., call 744-4397.Chat with Kovac and Womack at noon Monday