“A Cool Desert Morning”: Dateline Reports on Susan Winters Homicide April 18 2025

On Friday, April 18, 2025, Dateline NBC airs “A Cool Desert Morning”, a compelling episode that revisits the 2015 death of Susan Winters, a mother, attorney, and wife from Henderson, Nevada. Initially deemed a suicide, her death would eventually lead to a years-long investigation, a family-led pursuit for justice, and the shocking unraveling of a double life. Correspondent Josh Mankiewicz guides viewers through the twists of the case, which began with a questionable suicide and ended with a manslaughter conviction.

The episode includes interviews with law enforcement, journalists, and the Winters family as they piece together the truth behind Susan’s final hours. At its heart is a haunting question: did Susan take her own life, or was her death a calculated act by someone she trusted most?

The Life and Promise of Susan Winters

Susan Winters was raised in Oklahoma and stood out as a gifted student-athlete, excelling in track, basketball, and softball. Described by her family as driven and determined, she carried those same qualities into adulthood, becoming a successful attorney. She later moved to Nevada, where she practiced law in the Las Vegas area while raising a family.

Years earlier, Susan had harbored a high school crush on Gregory Brent Dennis, a quarterback four years her senior. They went their separate ways after graduation, only reconnecting years later thanks to Susan’s sister-in-law. Their rekindled connection led to marriage in 1995 and the birth of two daughters. From the outside, the couple appeared to have built a stable life, but in private, troubling cracks had begun to show.

A Sudden Death and a Suspicious Explanation

On the morning of January 3, 2015, Dennis called 911 to report that Susan was unresponsive. Emergency responders were able to restore a faint pulse, but Susan was declared dead later that day at a nearby hospital. According to Dennis, his wife had attempted suicide by ingesting antifreeze and oxycodone. He claimed she had been depressed, was taking anti-anxiety medication, and had previously attempted suicide during a temporary separation in 2012.

The Clark County Coroner ruled her death a suicide based on the toxicology report, which showed fatal levels of ethylene glycol and oxycodone. Henderson police closed the case shortly afterward. However, Susan’s family rejected the suicide ruling, convinced it did not align with her character, recent behavior, or the circumstances of her death.

A Family’s Fight for the Truth

Unable to accept the official explanation, the Winters family launched a private investigation. They hired a well-regarded criminal defense attorney and a private investigative team. Within days of Susan’s funeral, Brent Dennis was placed under surveillance. Investigators documented his frequent trips to The Orleans casino, where he often met with a man previously convicted on drug charges. These findings suggested Dennis was hiding a drug addiction — a significant detail that had never come up during the initial police investigation.

The family’s concerns deepened as more details emerged. Dennis had deposited a check for $180,000 written from Susan’s private account into their joint account just days after her death. He had also quickly moved to claim Susan’s $1 million life insurance policy and obtained full control of her shares in the family’s restaurant business.

Building a Case: Financial Motive and Forensic Evidence

With the civil case underway, the Winters family gained access to Dennis’s phone records and financial documents. Those records placed Dennis outside the home in the early hours of the morning Susan died, despite his claim he’d been asleep beside her all night. Investigators found he had driven to meet his drug dealer at The Orleans hotel around that time.

During a deposition, Dennis admitted to using controlled substances and acknowledged that Susan had threatened to report him, potentially costing him his psychologist license. He insisted that they had written the $180,000 check together and maintained his belief that Susan had died by suicide. Susan’s daughters supported their father’s version of events, testifying that their mother had battled depression for years.

However, the deposition raised further doubts about Dennis’s credibility. Attorney Tony Sgro noted that Dennis struggled under questioning and could not offer consistent explanations. These inconsistencies, combined with the financial transactions and toxicology findings, prompted the Winters family to take their case to the Clark County District Attorney.

A Reopened Investigation and Criminal Charges

In 2016, Prosecutor Marc DiGiacomo agreed to reopen the case. A review of Dennis’s phone revealed audio recordings of heated arguments between him and Susan. In one, Susan could be heard saying she didn’t want to enter her fifties “with someone who hates me as much as you do.” The tone and content of these exchanges painted a picture of a marriage in crisis.

Further forensic analysis supported the theory that Dennis had attempted to poison his wife with antifreeze, and when it wasn’t working quickly enough, he supplemented it with a fatal dose of oxycodone. The fact that Susan did not have a prescription for the drug and that no oxycodone bottle was found at the scene added weight to this conclusion.

Dennis was arrested and charged with murder in 2017. After several delays, including pandemic-related court slowdowns, he entered an Alford plea in 2022 to voluntary manslaughter. He received a sentence of three to ten years in prison.

Justice in Criminal and Civil Court

Though the Alford plea did not require Dennis to admit guilt, it acknowledged that prosecutors had sufficient evidence to convict him. For the Winters family, the plea brought some measure of accountability but did not erase the trauma of losing Susan under such circumstances.

In 2023, a civil court found Dennis liable for Susan’s wrongful death and ordered him to pay just over $1 million in damages to her family. The ruling echoed what Susan’s loved ones had believed from the beginning: her death was not a suicide, but the result of a deliberate act by someone she once trusted.

A Legacy of Persistence and Grief

“A Cool Desert Morning” is more than a story about a criminal case; it is a portrait of a family that refused to give up. Susan Winters’s parents, brother, and sister-in-law never stopped fighting to uncover the truth. Their determination exposed a hidden world of deceit and ultimately led to legal consequences for the man they believe took Susan’s life.

Although justice was served to some extent, the Winters family continues to live with the pain of what happened. As Susan’s father, Danny Winters, said in a heartbreaking interview, “There ought to be a special place in hell for him and I hope he goes there.” This Dateline episode ensures Susan’s story is not forgotten — a reminder of the power of perseverance and the search for truth.