Stacey, the daughter of Jerry Daniels and Judie Eaton, met Michael Wallace when she was 17, in 1985, and they bonded immediately. The couple married and had their first daughter, Ashley, in 1988. In 1991, they had a second daughter, Bree.

In late 1999, Wallace began feeling intermittently ill. Family members variously remember him as acting unsteady, coughing and seeming swollen. As his inexplicable sickness persisted over the holiday season, his family encouraged him to seek medical care, but he died in early 2000 before he could do so. Their daughter Ashley was 11 at the time and had been alone with him. She blamed herself for his death. She had noticed his ill appearance that day, but thought nothing of it. Physicians told Castor that her husband had died of a heart attack. Although Wallace’s sister was skeptical and requested an autopsy for Wallace, Castor refused, saying she believed the doctors were correct.

In 2003, Stacey married David Castor, whose surname she used from then on. Castor was the owner of an air conditioning installation and repair company, and Stacey served as his office manager. In August 2005, at 2:00 p.m. one afternoon, Castor called her local sheriff’s office to tell them that her husband had locked himself in their bedroom for a day following an argument and was not responding to his cell phone. When he did not appear at their shared workplace, she had become worried. She claimed he was depressed. Unable to get a response, Sergeant Robert Willoughby of the Onondaga County Sheriff’s Department kicked in the door of the bedroom and found David Castor lying dead. Among the items near his body were a container of antifreeze and a half-full glass of bright green liquid. Willoughby says he remembers that Castor screamed, “He’s not dead, he’s not dead.”

“In 2005, people started to put it together,” Cayuga County Sheriff Dave Gould said. “If Mr. Wallace had been cremated, or if Mr. Castor had not died, we would never have known we had a homicide.”

In September 2007, amid mounting evidence that Castor had murdered both of her husbands, she began to panic. After she learned police had exhumed Wallace’s body and found traces of antifreeze in his system, she was believed to have devised a plan to set up her daughter Ashley for the murders.

For two years, investigators had collected evidence against Castor for the deaths of her husbands. In 2007, she was arrested for second degree murder in David’s death and for attempting to murder Ashley and frame her for the murders of David and Wallace.

Forensic Files had an episode titled “Freeze Framed” regarding Castor. In addition to the Turner and Castor antifreeze murder cases, similar cases were reported in 2008. In 2002, a man had been convicted of murdering his wife by antifreeze in 1998. A letter she had written before her death incriminated him as the murderer if she were to die eventually; the letter led to his prosecution. Series Sex Lies and Murder, series 2 episode 3 as well as describing the events leading to the trial included an interview with the district attorney in the case who pointed out Castor may have murdered her own father, Jerry Daniels, who died 22 February 2002, shortly after his daughter visited him in hospital where he had a minor lung complaint. Castor’s first husband’s family believe Castor may have killed her father having brought an open can of soda in for her father to drink in hospital. She was the executor of his estate.

On February 5, 2009, Castor was found guilty of second degree murder in the poisoning death of David and of attempted second degree murder for overdosing her daughter Ashley with drugs and vodka. With a “jam-packed” courtroom, most were focused on Castor. She, however, had her eyes closed as the verdicts were read. Her lead defense counsel, Keller, announced that Castor would appeal the verdict, including challenging the inclusion of evidence regarding the death of her first husband, for which Castor had not been charged.

On March 5, 2009, at Castor’s sentencing, Chief Assistant District Attorney Christine Garvey asked Fahey to impose the maximum consecutive sentences because of the brutality of David’s death. Further, she criticized how Castor had “partied in her backyard with friends like nothing was happening” as Ashley was comatose in her room. “She is cold, calculating and without any emotion for what she has done,” she stated. “Human life is sacred. Stacey Castor places no value on human life, not even her own flesh and blood. To Stacey Castor, human beings are disposable.”

On April 24, 2009, ABC aired a two-hour 20/20 special about Castor and the trial, which included interviews. During the trial, Castor had been dubbed “The Black Widow” by media outlets, a title previously given to Lynn Turner. Ashley said that she does not know how her mother, any mother, could try to kill her own child, a question that the public has also pondered. Castor, who professed to being shocked at the guilty verdict, maintained her innocence during the on-air 20/20 special, as well as in unaired parts of the program. She said that “Ashley brought this on” and insists that she and Ashley know what really happened. She did express sympathy for her daughter Bree. She called Bree an innocent victim, whom she lost along with her freedom and her husbands. She indicated that her mother, stepfather and some other relatives still support her.

ABC interviewed forensic psychiatrist Dr. James Knoll for psychological perspective on the case and he answered viewers’ questions via video on April 23, 2009, and via site comments on April 27, 2009. He stated that while most suicide notes focus on themes of remorse and the person not being able to go on with life, the note supposedly written by Ashley was focused on taking the blame off of Castor. He said that this theme was repeated fourteen times within the note and that he believes Castor will never admit to guilt of the murders. The code of murderers such as these, he said, is “deny, deny, deny” until the bitter end. When asked if Castor’s behavior and body language on the stand shows any sort of clue about her mental state and guilt, Knoll reminded that body language and behavior can be affected by events during a trial (such as “side effects of medications, anxiety, fatigue and attorney instructions to the defendant on how to behave”) and that their interpretation is not always reliable.

Stacey Castor’s story was adapted in into the Lifetime film, Poisoned Love: The Stacey Castor Story, as part of its “Ripped from the Headlines” feature film series that aired on February 1, 2020. The film stars Nia Vardalos as Stacey Castor.