Kellie Martin and her husband Don were taking Christmas decorations down from the attic of their suburban Garland, Texas, home in late 2011 when their lives changed forever.

Kellie, 54, missed a step on a ladder and fell, resulting in a herniated disk in her back. After physical therapy and muscle relaxers, their family doctor recommended neurosurgeon Christopher Duntsch. The couple agreed to visit the doctor — a decision that will forever haunt Don and their two daughters.

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The case of Duntsch is explored in the new Oxygen docu-series, “License to Kill,” premiering on June 23. The show, hosted by renowned plastic surgeon Dr. Terry Dubrow of “Botched," chronicles the harrowing accounts of patients put into jeopardy by medical professionals’ insidious use of their expertise. It highlights interviews with families, medical professionals and law enforcement.

Don Martin participated in the Oxygen docuseries "License to Kill."

Don Martin participated in the Oxygen docuseries "License to Kill." (Oxygen)

Duntsch was recently the subject of a true crime podcast earlier this year titled “Dr. Death” by Wondery — the same podcast network behind their hit series “Dirty John.”

“From the initial fall, it wasn’t that super great,” Don told Fox News about his wife’s injury. “It was a lingering pain. It never went away. We did all kinds of treatments to help alleviate the pain, but it just remained persistent. We were planning on going to an out of country trip, so we thought we might get this fixed before we did. And she was in more pain than she led on. I could see it. I didn’t want her to go through that if we could avoid it. That’s when we started exploring surgery options.”

The couple soon found themselves in Dr. Duntsch’s office scheduling surgery for during the elementary school teacher’s March 2012 spring break. Duntsch insisted the 45-minute procedure was routine and simple to do.

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Dr. Christopher Duntsch. — Matt Goodman for D Magazine / Courtesy of Oxygen

Dr. Christopher Duntsch. — Matt Goodman for D Magazine / Courtesy of Oxygen

“He sounded very articulate,” reflected Don. “It sounded like he knew what he was doing. We figure it wouldn’t be an issue… He said it was a minor surgery, but that she would be OK after the procedure. A very simple, common procedure — that’s what we were hoping for. A quick recovery."

But on the day of surgery, Don found himself waiting, not knowing what happened to Martin.

“About an hour later, I’m still sitting in the waiting room and I hadn’t heard from anybody,” he explained. “I asked one of the nurses to check and see what was going on. Then 15-20 minutes later, [Duntsch] came out. He tells me the surgery went well and she’s moving around, but was in obvious pain so they gave her more medicine. She may have to go up to the ICU or maybe stay overnight, but she was going to be OK… That’s when I called my daughters to come up to the hospital. That’s when I realized this is not good.”

The wait continued and Don agonized over Martin, wondering what was happening behind closed doors.

Kellie Martin and her family. — Oxygen

Kellie Martin and her family. — Oxygen

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“I’m starting to freak out,” he said. “Something just wasn’t right because no one was telling me, ‘Hey, she’s recovering, you can come to see her.’ Instead, they’re continuing to work on her. This is going on now for two hours. My girls were holding on to hope, but I just knew something was seriously wrong."

Don said the ICU physician, as well as Duntsch and the anesthesiologist, came to see him and the couple’s two daughters to deliver the devastating news — the beloved matriarch was dead.

“They told us they tried everything they could, but they couldn’t save her,” said Don. “That’s when the girls lost it. I lost it. That’s when the nightmare started… We didn’t get a chance to say goodbye to her. We went in there with good faith, believing in the doctors and the medical world so they could help us. Instead, they ended up turning our world upside down. It was pure misery. I was totally lost. My world just ended right then and there.”

Don Martin said he and his daughters are still trying to make sense of what happened to beloved matriarch Kellie Martin. — Oxygen

Don Martin said he and his daughters are still trying to make sense of what happened to beloved matriarch Kellie Martin. — Oxygen

People magazine reported the medical examiner confirmed Don’s fears. It turned out Martin had bled to death after Duntsch sliced an artery. According to the outlet, Don also learned that Duntsch had earlier operated on one of the coroner’s office employees and left the man paralyzed. The Dallas County district attorney’s office would later learn that that out of 38 surgeries undertaken by Duntsch in less than two years, 33 had gone wrong. Two patients had died, one was rendered a quadriplegic and many were left with permanent injuries.

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“I was angry,” said Don when he learned of Duntsch’s other victims. “I was angry at the medical world. If this doctor had previous bad outcomes, why did he still had the ability to do surgery? It was such a cover-up. As things progressed, I got angrier and angrier with the system. But by the grace of God, other doctors started voicing their opinions about [Duntsch]. But how was I going to survive? How am I going to live day by day now?”

Between 2011 and 2013, Rolling Stone previously reported, Duntsch was employed by four Dallas-area hospitals and nearly all of his patients, those who survived, came out in far worse shape than ever before.

Don Martin still wonders why Christopher Duntsch was able to get away for so long.

Don Martin still wonders why Christopher Duntsch was able to get away for so long. (Oxygen)

During the trial, Dallas surgeon Randall Kirby, who assisted on one of Duntsch’s surgeries in 2012, told jurors he sent information to the Texas Medical Board, warning them of Duntsch’s botched procedures. D Magazine shared that despite receiving complaints dating back to 2012, the Texas Medical Board reportedly didn’t revoke Duntsch’s privileges until 2013. Texas Observer clarified that the Texas Medical Board is "limited" in its ability to investigate malpractice, which could have possibly resulted in the delay.

According to records, Duntsch was booked into the Dallas County Jail in 2015. He was charged with five counts of aggravated assault causing serious bodily injury and one count of injury to a child, elderly or disabled person.

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D Magazine reported that in July 2016, the Dallas County District Attorney’s Office followed through and a grand jury returned five indictments of aggravated assault and one of harming an elderly person. Duntsch pleaded not guilty and alleged in emails that he was at the center of “a vast conspiracy to bilk money from the hospitals where he practiced.”

Dallas-based surgeon Christopher Duntsch was also the subject of a Wondery podcast titled "Dr. Death."

Dallas-based surgeon Christopher Duntsch was also the subject of a Wondery podcast titled "Dr. Death." (Dallas County Jail)

The indictment accused Duntsch of wide-ranging malpractice, including improper placement of screws and plates along patients’ spines, a sponge left in one patient, and a major vein cut in another. Records also showed that Duntsch operated on the wrong part of a patient’s spine, damaged nerves and left one woman with chronic pain and dependent on a wheelchair.

At the time, Duntsch was struggling financially and had racked up a series of arrests, including stealing Walmart merchandise.

During the trial, prosecutors said Duntsch’s hands and surgical tools amounted to “deadly weapons,” and contended that he “intentionally, knowingly and recklessly” harmed up to 15 of his patients. Prosecutors also claimed that in a 2011 email to a girlfriend, Duntsch said he would “become a cold-blooded killer.”

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Dallas surgeon Randall Kirby says his former colleague, Dr. Christopher Duntsch, managed to commit crimes so heinous that patients everywhere are still struck by fear when they hear about the case for the first time. — Oxygen

Dallas surgeon Randall Kirby says his former colleague, Dr. Christopher Duntsch, managed to commit crimes so heinous that patients everywhere are still struck by fear when they hear about the case for the first time. — Oxygen

However, Duntsch’s attorneys argued that he was not a criminal but just a lousy surgeon committing malpractice in chaotic operating rooms in hospitals in Dallas and its northern suburbs. They also said the tone of the email in question was unclear and could have been meant as sarcasm.

The New Yorker reported Duntsch was ultimately stopped after the combined involvement of the Dallas Country district attorney, an attorney, a journalist, and the state medical board with the efforts initiated by Kirby and Dr. Robert Henderson, a veteran surgeon at the Dallas Medical Center.

In 2017, a jury sentenced Duntsch to life in prison for maiming patients who had turned to him for surgery to resolve debilitating injuries. The decision came almost a week after the Dallas County jury convicted Duntsch of first-degree felony injury to an elderly person.

But life for Don and his family still isn’t easy.

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“I’m not gonna lie, I think this puts a strain on our relationship a little bit,” said Don about his daughters. “We were such a close-knit family. It was difficult for them. It was difficult for all of us. They were trying to be careful around me, trying not to say anything or do anything that will upset me. My whole lifestyle has changed. Everything is different now. I look at life differently totally differently. Life is just too precious, too short. We can’t take the little things for granted. We’re just trying to make the best of each day.”

Don hopes viewers will be compelled to conduct no-nonsense on any physician or surgeon they’re considering — and to never take any kind of procedure for granted.

“Get a second opinion no matter what,” he said. “Evaluate everything to make sure you really want to do this surgery. Explore all options. And realize that no surgery is a routine, simple surgery. Everything can be a life or death situation.”

"License to Kill" premieres June 23 at 7 p.m. on Oxygen. The Associated Press contributed to this report.