Stella Maudine Nickell (née Stephenson) was born on August 7, 1943, in Colton, Oregon. Her early life was shaped by poverty and a turbulent family environment. She grew up with very little stability, and by the time she was a young woman, she was already making serious choices that would land her in trouble. In 1959, after giving birth to her first daughter, Cynthia Hamilton, she relocated to Southern California. There, she married and gave birth to another daughter.

Stella quickly gained a reputation for being on the wrong side of the law. In 1968, she was convicted of fraud and served six months in jail. The following year, she was charged with child abuse after beating her daughter, Cynthia, with a curtain rod. The courts ordered her into counseling. In 1971, she was convicted of forgery, cementing a long trail of petty crimes.

In 1974, she met Bruce Nickell, an equipment operator who suffered from alcoholism. The two married in 1976 and tried to build a life together. At first, their drinking habits kept the bond strong, but tensions rose when Bruce decided to get sober. The shift caused friction in their marriage. As Bruce stopped drinking, Stella felt increasingly disconnected from him, turning to other interests like working as a security screener at Seattle–Tacoma International Airport and tending a home aquarium. By the mid-1980s, their once chaotic bond was coming apart, setting the stage for a darker chapter in both their lives.

On June 5, 1986, Bruce Nickell came home complaining of a headache. He took four Excedrin capsules from a bottle in their home and collapsed soon after. He was rushed to Harborview Medical Center, but doctors were unable to save him. At the time, his death was attributed to natural causes. Six days later, tragedy struck again when 40‑year‑old Sue Snow took two Excedrin capsules for a headache and was found unresponsive by her teenage daughter. Paramedics arrived and transported her to the hospital, where she died the same day.

An autopsy revealed the unmistakable scent of bitter almonds, indicating cyanide poisoning. Tests confirmed that both Sue Snow and the Excedrin bottle she used contained lethal cyanide. The case quickly became a media sensation and triggered a massive recall. Bristol‑Myers pulled all Excedrin products from the shelves and offered a $300,000 reward for information leading to the arrest of the person responsible.

Stella came forward, claiming that her husband had died after taking pills from a bottle with the same lot number as the contaminated Excedrin. FDA testing confirmed that Bruce Nickell had been poisoned by cyanide. What initially appeared to be a consumer tampering case soon began to shift focus to Stella herself. Authorities discovered that she had purchased an algaecide called Algae Destroyer from a local fish store. Traces of this same algaecide were found mixed with the cyanide in the contaminated capsules, suggesting that she had used the same container for both.

Stella refused to take a polygraph examination and quickly drew suspicion when authorities learned she stood to gain roughly $176,000 in life insurance payouts for Bruce’s death. Even more damning was the fact that she had forged her husband’s signature on at least two policies. In early 1987, her daughter Cynthia came forward with a shocking statement: she claimed that her mother had tried to kill Bruce before, using foxglove hidden in capsules, and had openly talked about poisoning him for insurance money. When investigators checked the Auburn Public Library records, they found that Stella had borrowed books on poisonous plants and never returned one of the texts, which contained information about cyanide poisoning.

On December 9, 1987, a federal grand jury indicted Stella Nickell on five counts of product tampering, including two resulting in death. At her trial in April and May of 1988, she was found guilty of all charges. The jury deliberated for five days before reaching a verdict. Stella received two 90‑year prison terms for the deaths of Bruce Nickell and Sue Snow, as well as three 10‑year terms for other tampering charges. All sentences were to run concurrently. The court also ordered her to forfeit remaining assets and pay a small fine.

Although she has appealed her conviction multiple times — citing jury misconduct and evidence withheld by the FBI — the verdict has been upheld. In 2017 and 2021, parole boards denied her release. In 2022, she petitioned for compassionate release due to failing health, but that request was also refused. As of November 2024, Stella Nickell remains imprisoned at FCI Hazelton, serving a sentence that will keep her behind bars until at least 2043, when she will be 99 years old.