Ah! Now, Elizabeth vargas and David Muir. Tonight, perhaps you've seen it yourself. Heated tempers in your own neighborhood. But now, neighbors losing it. And you'll hear the heart-pounding 911 calls,... See More
Ah! Now, Elizabeth vargas and David Muir. Tonight, perhaps you've seen it yourself. Heated tempers in your own neighborhood. But now, neighbors losing it. And you'll hear the heart-pounding 911 calls, the girlfriend who heard her boyfriend shot in front of her. Matt Gutman has the story. Reporter: In the lush green hills of genteel encinitas, California, a toxic tale of shrubbery. The invasive Brazilian pepper tree, and two men losing it. In a dispute over clearing the poisonous bushes from a driveway. 99 emergency. My partner just got shot. Please come to lone jack road. Please hurry! He's bleeding, got shot in the head. Reporter: For Evelyn Zeller, March 28, 2013, began as a beautiful day. They're all beautiful days here in the San Diego suburbs. That morning she awoke in the master bedroom of this rented Spanish contemporary and shared a tender moment with her boyfriend, John Upton. It was my birthday. John woke me up to wish me a happy birthday. Reporter: She says Upton, still in his pajamas, headed outside to make room for two day laborers clearing brush on the driveway of their neighbor, Michael vilkin. John went out to offer to move the car? Yes, yes. Reporter: To understand what happened, you need to understand the lay of the land. Upton lived here. Vilkin owned the adjacent undeveloped 2.6 acre lot, including this narrow strip -- his future driveway. The problem was these Brazilian pepper trees along that strip had become a creeping menace. Choking off access. And vilkin needed them gone. On this morning, Upton's Mercedes SUV is parked beside the trees on vilkin's land. He wanted to move the car to give them more space to trim the trees. Reporter: A couple of minutes later, Evelyn gets up to follow him outside. I had set foot on the first step right there as I heard the shots. Reporter: Using this massive .44 magnum revolver, vilkin shoots 56-year-old John Upton once in the midsection, followed several seconds later by a second shot to the head, execution-style. So, I look up the path, and I see John lying on the path. Reporter: And you instantly knew he was dead? I felt he was dead. And suddenly I hear vilkin go, "Don't get any Closer." And he has the gun pointed at my chest. Yeah, the crazy, crazy dude. He's got a gun. Oh my god! What a Nut. He's still got a gun, man. You gotta be careful. Reporter: None of it makes sense. Murders just don't happen around here in encinitas, and neither of these men were magnets for trouble -- certainly not the diminutive, cerebral and hard-working Michael vilkin. It was a shock, to imagine Michael was the one to do that. Reporter: The neighbors were aghast. I talked to him all the time. He was friendly to us. He let us park on his lot. Reporter: Tamara vilkin, vilkin's wife and companion for the past 30 years stands by her man. Michael has a beautiful heart. And other people saying that, too. It's not me saying that. Reporter: They were god-fearing immigrants who fled the former communist soviet Georgia to chase their American dream. They bought this vacant land on lone jack road after years of scrimping and saving from his past fledgling career as an economist and hers as a piano teacher. Did he have any hopes or dreams for that land? Yes, we wanted to build a house over there and probably retire over there. Reporter: Vilkin spent every minute he could spare working the land the old-fashioned way, with shovel, wheelbarrow, axe and saw, lovingly nursing it to health for the day when they could build their dream home. He was there every day for 8 to 10 hours a day, tending to his empty lot, cutting things down, moving dirt around. Reporter: As for vilkin's neighbor John Upton, a 6'2", 235-pound teddy bear of a man, he wasn't just a hero to his children John and Elizabeth. So many fond memories. So many memories. And you look at like, in a span of 56 years of how many things he accomplished. And how he's impacted the world. Hello! Hello! Reporter: To many he was practically a saint. This is "20/20." From ABC news -- Reporter: As reported here on "20/20" in 1993, Upton was a documentary filmmaker who made it his personal mission to rescue Romanian orphans. The government has put these kids on the back burner. For god's sake, let me help these kids. I really knew from a very very young age that you really can make a difference because I saw my dad do it. Reporter: Since then, he'd settled down here with his girlfriend Evelyn, a new-ager enthralled with Upton's zen. We love buddhas, we love serenity, and peacefulness and inspiration. Reporter: So where did it all go wrong? The answer is in the poisonous trees on that narrow strip of vilkin's land. Upton liked them. But remember, vilkin wanted them gone, and his interest in landscaping bordered on obsession. I questioned why he spent so much time on the lot. Reporter: He just seemed eccentric? He just seemed a little eccentric, yeah. Reporter: Others chose a different word. I think his behavior was absolutely bizarre. Who buys a site and then hangs out on it and works on it 10, 12 hours a day when the same amount of work can be done in a day with a bulldozer? It doesn't make any sense. None of what he did was permitted. This was a landslide property, it wasn't safe for the neighbors. Reporter: Despite those concerns, Evelyn says Upton never complained about his neighbor. He used to say many times, "Wow, I admire his work ethic." I talk to my dad forever. Reporter: Did he ever mention vilkin? I've never even heard that name in my entire life. Reporter: And yet, surely something happened to provoke that brumil hocide on the morning of March 28th, something that would make the egghead immigrant "Lose it." Hurry up! Hurry up! Hurry up. He's dead! I think he's dead! Hurry up, please! Reporter: Before she called 911, before she even approached the crime scene, Evelyn Zeller noticed something odd about the shooter. When you came out, he first saw you. What did he do? He seemed to be on the phone. Reporter: It's not often that the killer calls in the homicide he's just committed, but that's exactly what happened here. Emergency. I need a detective here. What's going on there? Well, the neighbor assaulted me and I shot him. Reporter: In theory, vilkin did the right thing. He shoots someone, calls 911. And yet, there was something sort of cold and callous about the call. You shot him? Yes. Like, with a gun? Yes. Where is the gun right now? I have my gun. And don't worry about it. When the sheriff comes it will be in the gun case. I am a responsible person. Don't worry about it. Reporter: Within minutes sheriff's deputies arrive to find vilkin still on the phone with the 911 operator. Put the phone down! Put the phone down! Reporter: He's arrested, but remains cool. And so confident that the next day he agrees to talk with our San Diego affiliate KGTV, expressing no remorse, but shockingly he does express disappointment with the performance of the massive handgun he used to kill John Upton -- this .44 magnum, because it failed to drop him with one shot. But somehow he made two or three steps. And I was in disbelief. I shot him in the head. Reporter: Michael vilkin's mission to rid his driveway of Brazilian pepper trees had somehow opened a door to a dark place in his mind where he could justify taking a man's life. Who is this guy? This man who murdered my father in cold blood. For what? Reporter: For good reason, says vilkin. I expect justice will be done. Reporter: Because, as he is about to tell us, John Upton was no saint. But a menace who terrorized him. Like this. Stop cutting trees! Reporter: What you're saying is that John Upton deserved to
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