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Crime News Snapped

Missouri Woman Convinces 20-Year-Old Boyfriend to Murder Her Ex-Husband, His Spouse

Snapped untangles the web of lies and complex plot that led to the deaths of Alex Chute and Brianna Sproul.

By Grace Jidoun

The latest episode of Snapped draws viewers into a dark world of bitter custody battles, toxic relationships, and murder. In November 2020, a young couple was fatally shot on the front porch of their home in Willard, Missouri, their bodies riddled with so many bullets investigators thought a wild gunfight had occurred. A four-year-old girl was found hiding in a bathroom unscathed.

Alex Chute and Brianna Sproul Found Dead

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On the morning of November 14, 2020, police received an alarming call: a woman spied two dead bodies on her neighbor’s front porch.

The bedroom community of Willard lies 12 miles outside of Springfield, and “to find anybody dead in that manner is something almost unheard of,” local police major Shannon Shipley told Snapped.

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The engaged couple, Alex Chute and Brianna Sproul, lived in the house with Alex’s young daughter from a previous marriage.

A loaded 40-caliber gun was found inches from Alex’s hand. With one gun and two dead bodies, it looked like a murder-suicide at first glance, said Shipley, but when first responders found shell casings from a second gun around the body, “it dispelled that theory pretty quickly.” The police whisked away Alex’s unharmed daughter and put her into protective services until they could piece together what happened.

Odd details immediately caught the attention of the eagle-eyed detectives. Alex’s gun was still fully loaded. Clearly, he had not fired it. “It indicated to me that he did not try to protect himself when he fell,” noted Shipley. Additionally, a loaded shotgun was strangely stashed behind the front door. “As a parent, I wouldn’t leave a loaded shotgun behind a door where it was accessible to a child, so that told me at least Alex and Brianna thought they needed some kind of protection,” Shipley told Snapped.

Police surmised that the couple trusted the perpetrator enough to leave the shotgun behind when they walked out to the porch. It was “like the victims had a personal connection with this person that allowed them to be so close to them,” said police sergeant Steve Purdy.

The crime was strange enough. But in a matter of a few days, the police had unraveled a complex scheme to take out Alex. At the center was Theresa Cox, his ex-wife and the mother of his child.

Alex and Theresa's Marriage

Theresa Cox featured on Snapped episode 3318

Alex and Theresa met in high school in upstate New York. They bonded over being transplants from other states — Alex hailed from Missouri, and Theresa was from North Carolina. “Theresa had a troubled upbringing and was raised by her grandmother,” noted Alex’s dad, Darrell Chute. Alex (and his siblings) had also lived with his grandmother after his parents divorced.

“They were pretty much together all the time, every day. Alex was very smitten with her,” recalled his mother, Lisa Pini.

It was a whirlwind relationship, and the two tied the knot right after high school. The newlyweds moved back to Missouri with Alex’s family, and within a few years, he enlisted in the Army and joined the National Guard. Just as he finished basic training, Theresa gave birth to their baby girl in May 2016. However, when Alex was deployed to Poland for a short mission, the young mom began to struggle, and the family had to step in to take care of the baby.

“I don’t think Theresa understood what being a mother was… she didn’t have a maternal bone in her,” proclaimed Alex’s sister, Valerie Matherne.

By 2019, the couple was divorced and sharing joint custody of their daughter. Trying to keep things amicable, Alex let Theresa keep their house.

Meanwhile, Alex got a job at a pizza restaurant and struck up a romance with co-worker Brianna Sproul. The two just “clicked,” remembered his dad, and they eventually moved in together.

“A big part of Alex loving Brianna so much was the way that she treated his daughter,” said his sister Katie.

His mom, Lisa, added, "Brianna took care of [his daughter] like she was her own; she loved her and made her birthday cakes and costumes for Halloween.”

RELATED: "Abused" Wife Fatally Shot Husband, Had Body Buried on Farm a Week After Taking Out Protective Order

Police establish a timeline and motive

As luck would have it, an officer lived 700 feet from the crime scene, and his doorbell recorded the sound of gunshots in an eerie video clip played on Snapped. The police had pinpointed the time of the murder: 1:21 am. Willard was such a safe community that “a lot of people discounted what they heard and never called,” said Shipley, adding others likely thought it was fireworks.

Photos on Snapped show the inside of the home as it appeared when police arrived: no sign of forced entry, and unlocked doors. A fanny pack with two Glock magazines sat in plain view on a table right by the door. Shipley, however, found something else that stopped her in her tracks: old paperwork regarding an ongoing custody battle in which Alex was trying to gain full rights to their daughter. “Right then, it really focused our attention on [Theresa’s] involvement,” recalled Shipley.

Matthew Plumb speaks to investigators

But Theresa had an alibi: she worked a late shift at Pizza Hut that ended at 1:00 am, and she was home by 1:30 — her boss, Matthew Plumb, corroborated the story to the police. He also mentioned the “bad blood” between Theresa and Alex, adding that she allegedly once told him she wanted Alex dead. Police obtained a search warrant and seized Theresa's cell phone, and the data backed up her alibi, but suspicious text messages in the days leading up to the murders concerned Purdy. 

One text stated: “Change of plans for Friday.” The response was, “I need some time to myself. I need to be able to air out my mind before tomorrow night.”

Theresa was texting with her 20-year-old boyfriend Duncan Bogle, who was eight years her junior and, according to friends, extremely impressionable. “Duncan was definitely the perfect mark for her. Generally, he always wants to do what makes other people happy. It made him an easy target,” lamented his friend, Henryedda Colvard.

Duncan’s cell phone data put him near the crime scene on the night of the murders. It was enough for police to pull a warrant to search the home he and Theresa shared. Police hit the jackpot, finding an empty box for a 9-millimeter gun, a receipt in Theresa’s name, and a safe filled with ammunition that matched the shell casing found at the crime scene.

But there was another twist yet to come. Theresa received an odd message on her phone from the girlfriend of her boss at Pizza Hut — the man who gave her an alibi — that led investigators to believe he was somehow involved.  In the police video on Snapped, we see Matthew Plumb cracking under police questioning as he admitted to conspiring with Theresa. According to Matthew, Theresa complained that Alex abused her child and sold him a story that she needed to protect her. He even advised her to report the gun stolen before the murder. 

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Who gunned down Alex and Brianna?

But it was Brianna’s boyfriend Duncan who ambushed the couple. "Her narrative was Alex is a bad person… abusive. Nothing that was ever founded. But those negative things probably make Matt or Duncan Bogle feel like he was helping her out, and not just harming someone who is truly innocent,” said prosecutor Philip Fuhrman.

Additionally, it was revealed that Alex had recently discovered that Theresa had been leaving their daughter home alone overnight while she went to work. “My brother called CPS, eventually they intervened, and he got full custody of their daughter,” said his brother Nicholas.

Theresa was served with paperwork from Alex’s attorneys cutting off child support the same day she reported the gun was missing.  “I believe it was the straw that broke the camel’s back,” remarked Purdy.

Matthew disposed of the murder weapon in a creek, which police were able to recover, and the gun’s serial number matched the box found at Theresa’s home. The crime lab determined casings at the scene came from that same gun.

The suspects go on the run

After Matthew was arrested and charged with first-degree murder, Theresa and Duncan disappeared, but within less than two weeks, police tracked them down on the streets of San Francisco, California. They had dyed and cut their hair and “were trying to blend in with the homeless people,” said Purdy.

They were charged with first-degree murder, but they both entered into a plea deal just before their trials were about to begin in October 2022. Ultimately, both pleaded  guilty to two counts of second-degree murder, and Duncan pled to an additional count of child endangerment. They were sentenced to two consecutive life terms in prison and will be eligible for parole in 2073.

In exchange for his testimony against Theresa, Matthew will spend eight years behind bars for conspiracy to commit murder and tampering with evidence.

Alex’s family is now raising his little girl.

Reflecting on the case, Shipley told Snapped, “She didn’t want her daughter. I think that she didn’t want Alex to have her daughter. I think she just wanted to wipe that side of her life away.”

Watch new episodes of Snapped at 6/5c on Oxygen on Sundays, and the next day on Peacock

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