Biannca Edmunds planned a murder to get rid of her ex-boyfriend over a custody dispute. Two people ended up dead, and it took years before she was finally held accountable.
Biannca was born on 22 March 1986 in Melbourne, Australia. Her childhood was unstable from the start. Her father was largely absent, and her parents divorced when she was six. He cut off all contact with the family after that.
Her mother remarried, and the family moved constantly across Melbourne, which meant Biannca kept switching schools and never really settled anywhere. Her grades suffered, and so did her mental health.
When she was around ten years old, her older brother began physically and sexually abusing her. He had been diagnosed with bipolar disorder, schizophrenia, and developmental difficulties, and was described as a troubled child who required a lot of care from his parents.
Biannca eventually told her mother what was happening. Her mother dismissed it completely, accused her of lying, and continued focusing on her brother as though nothing had been said. Biannca was left completely unprotected.
She was later diagnosed with severe anxiety and a self-defeating personality disorder, both connected to what she had experienced as a child.
She also dealt with serious physical health issues, including arthritis and carpal tunnel syndrome, both of which required medical treatment and surgery. She left high school early, joined the Navy, and was medically discharged after a short period.
After that, she bounced between jobs in retail, dental nursing, and reception work. She also moved from one relationship to another without much stability.
During one of those relationships, with a man named Dirk, she had her first child, a son named Tyler. That relationship eventually ended, and by 2012, Biannca had moved on entirely.
That year, she met Michael Caposiena. He was 35 at the time, nine years older than her. Things moved fast. Biannca and Tyler moved into his home, and within six months she was pregnant with his child.
Michael proposed, and they began planning a wedding. But the relationship turned toxic quickly. Court documents later described it as involving elements of family violence, though no specific details about the nature or direction of that violence were made public.
Before the engagement party even took place, the couple split up. Michael moved on and started a new relationship with a woman named Silvana Silva.
In June 2013, Biannca gave birth to Michael’s son, whom she named Luca. Michael then applied to the family court for visitation rights. Biannca opposed it at every stage, and an entire year passed before the courts made any decision.
By August 2015, Michael was finally granted supervised visits every other week, two hours at a time, at a neutral location.
Because Michael lived about four hours away from Biannca, she had to travel roughly two to two and a half hours each way to make those visits happen. She complied for a few months. Then she stopped and decided she needed a different solution entirely.
Around this same time, in 2015, Biannca began a relationship with Glenn Cassidy. Glenn was 48 years old, nineteen years older than her. He had just finalised a divorce after a twenty-year marriage and had three daughters.
People who knew him described him as naive, vulnerable, and easy to manipulate. He had barely been single for a few months before meeting Biannca.
Almost immediately, Biannca began feeding Glenn a negative picture of Michael. She told him Michael was violent and an unfit father. She then escalated the claims, telling Glenn that Michael planned to kidnap Luca and flee Australia permanently, and that he was also planning to kill both her and Glenn.
None of these claims were backed by any evidence. Glenn never questioned a single thing she said. He accepted all of it.
When verbal pressure failed to push Glenn toward action, Biannca turned to a more calculated approach. She began using sexual activity as a tool to psychologically condition him.
During intercourse, she would repeatedly bring Glenn close to climax and then stop, demanding he verbally agree to kill Michael before she would continue.
She introduced a firearm into these encounters as well, holding the weapon during sex while making explicit demands that Glenn carry out the killing. Over time, Glenn began associating the idea of the murder with physical pleasure. The conditioning worked.
Biannca and Glenn became engaged and started planning a wedding. She told Glenn she wanted to have a child with him and claimed she was undergoing fertility treatment, though this was never confirmed.
The couple married in February 2016. Shortly after, Biannca told Glenn she had suffered a miscarriage and blamed the loss entirely on the stress caused by Michael and the custody situation. Glenn accepted this without question, and it appeared to push him further toward acting.
Throughout this period, Glenn made several reconnaissance trips to Michael’s property. Each trip involved a round journey of over 100 miles. He would sit outside the house, observe the layout and the comings and goings, and then call Biannca from the car to give her updates.
What neither of them knew was that an application on Glenn’s phone was automatically recording every call he made. Every conversation he had with Biannca about the plan was captured in full.
In these recordings, Biannca’s controlling role was clearly audible. She directed the planning, maintained pressure on Glenn, and withheld affection as leverage.
Glenn also created a planning list on the notes application on his phone. It included headings such as obstacles and things to do before the job.
The two of them consistently referred to the planned murder as the job in all their communications, apparently believing this was enough to disguise what they were discussing.
On 12 March 2016, a text message was sent from Glenn’s phone to Biannca’s number. The message stated that Glenn was acting entirely on his own and that Biannca had no knowledge of what he was about to do.
Forensic analysis later confirmed that Biannca had written and sent the message herself using Glenn’s phone. She was constructing an alibi before the murder had even taken place.
That afternoon, Glenn drove to Michael’s property. Michael was not home, so Glenn waited. He had brought supplies with him for the wait. When Michael and Silvana returned home in the evening and settled inside for the night, Glenn got out of his car and began pacing outside the house.
Silvana saw him through the window, recognised him, and alerted Michael. By the time Michael looked outside, Glenn had moved out of view. Moments later, both Michael and Silvana heard noises coming from outside.
Michael, sensing something was wrong, armed himself with a kitchen knife before going to the front door. When he opened it, Glenn presented himself calmly, extending his hand for a handshake. Michael began to relax slightly and opened the door wider.
At that moment, Glenn forced his way inside. A violent struggle broke out immediately. Glenn reached into the bag he was carrying, pulled out a firearm, and aimed it at Michael.
Michael responded by stabbing Glenn multiple times in the torso with the kitchen knife, desperately trying to defend himself and protect Silvana. Despite the wounds, Glenn raised the gun and fired. Michael died from a single gunshot wound to the head.
After Michael was shot, Glenn turned toward Silvana. He chased her through the house and caught up with her outside the front door, where he raised the firearm and pulled the trigger. The gun jammed.
He then physically attacked her, throwing her to the ground and repeatedly striking her head against the concrete.
The attack stopped only when Glenn collapsed from the blood loss caused by the stab wounds he had sustained during the struggle with Michael. He died at the scene. Silvana survived but was critically injured and was hospitalised for four days.
Police arrived and assessed the scene. Both men were dead. Silvana was the only survivor. Officers initially arrested her upon her discharge from hospital before quickly ruling her out as a suspect.
Investigators then identified Biannca as the common link between both men and brought her in for questioning.
During the interview, Biannca denied everything. She said she had never wished Michael dead, had never asked anyone to harm him, and had no involvement in any plan.
She presented the text message Glenn had sent from his own phone as evidence that he had acted completely alone. Police accepted her account. The case was closed.
Biannca then began a new relationship with a man named Todd Bookham, who had previously served eight years in prison for violent offences against his former partner. She told him that Glenn had died of cancer.
She also applied to the courts for compensation from Michael’s estate and was awarded $300,000. Not long after, she gave birth to her third child.
When Todd later discovered the truth about how Glenn had actually died, he confronted Biannca. She gave him a full confession, admitting that she had been the driving force behind the plan to kill Michael. Todd eventually cooperated with investigators after police reopened the case.
When detectives looked more closely, they seized Biannca’s laptop and recovered substantial digital evidence. The automatically recorded phone calls between her and Glenn were retrieved in full.
The hand-drawn map of Michael’s property was found, and Biannca’s fingerprints were on it. Her fingerprints were also confirmed on the firearm Glenn had used. The planning records on Glenn’s phone were recovered as well.
Biannca’s trial began in June 2022, more than six years after the murders. The prosecution presented the recorded phone calls, the planning documents, the fingerprint evidence and Todd’s testimony about her confession.
The full extent of the psychological and sexual manipulation she had used to coerce Glenn was presented in court and formed a central part of the case against her. The jury found her guilty. Biannca Edmunds was sentenced to 26 years in prison.
