In 2002, Dianne Brimble boarded a cruise ship. She was found dead less than 24 hours later.

It's the morning of the 24th of September, 2002 and Dianne Brimble has yet to appear after her first night aboard a vacation cruise ship set for New Caledonia and Vanuatu. 

Dianne’s sister, Alma laughs it off to her daughter and niece, joking that Dianne probably had a bit too much to drink and fallen asleep on a deck chair somewhere in the sun.  

After all, the sisters had been planning this vacation for almost two years and everyone was more then ready to have a good time. 

The 10-day cruise began a day earlier, boarding in Sydney. After some welcome drinks on deck and dinner; Alma, her daughter and Dianne’s daughter Tahlia all retired for an early evening leaving Dianne to enjoy herself mingling with the other guests at the ship’s disco.  

That would be the last time they see Dianne alive. 

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After years of scrimping and saving, this vacation had brought out a different adventurous side to Dianne.

Universally known as a fun-loving, social person who enjoyed dancing and getting the party started. 

Her family and friends would use ‘conservative’ and ‘prudish’ to describe her romantic adventures, yet after one night aboard the cruise, her fellow guests found Dianne to be ‘forthright’ and ‘flirtatious.’

So when Dianne wasn’t in her bed the next morning, Alma was curious what she’d gotten up to, but not yet concerned.

That’s when an emergency call rang through all the cabins and Alma’s stomach dropped to the floor.

Following the sound of the alert, Alma was confronted with the sight of several medical staff trying to revive an unconscious woman on the floor of a cabin.  

After several resuscitation attempts, they announced Dianne Brimble dead less than 24 hours after she boarded what she was hoping to be a trip of a lifetime with her family. 

But whose cabin was she found in and how did she get there? The cabin belonged to a group of four men who were part of a larger group of eight and would soon become infamously known as 'The Adelaide Eight.'

There was a core group within this group who had a tighter knit friendship. They went to the gym together, worked in the nightlife industry together and a few had ties to gang activity and drug use.

Three of the eight men would eventually be charged with crimes associated with this case, but not the ones Dianne’s family hoped for.  

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Dianne boarded the cruise on the 23rd of September, 2002 alongside twelve of her own family members including her sister, niece and daughter. 

Dianne had been saving up for this trip for a long time which was no easy feat for a single mother of three when money was so tight.

A lot is unknown about the series of events between her family retiring for the evening and the discovery of her body the next morning, but what has been verified by several witnesses is that she fell into conversation with two men from 'The Adelaide Eight,' a man called Dragan Losic and Mark Wilhelm. 

What’s also known is that after the nightclub closed at four am, Dianne went back to Mark’s cabin and the pair had sexual intercourse. 

Sometime between then and the following morning, Dianne who was still in Mark’s cabin, laid down between the bunk beds and showed concerning symptoms that her body might shut down such as defecating herself. However, help wasn’t called until much later and by then was too late.

Upon arrival medical workers noted evidence of drugs in the cabin, which they reported as suspicious. Despite this, the cabin wasn’t sealed up to preserve the scene after Dianne’s death, like it should have been.

The four men living there were allowed to gather their belongings to be moved to another cabin and in doing so, may have moved and hidden a lot of evidence that could have been used against them.

Image: AAP (top left) Mark Wilhem, Matthew Slade, Dragan Losic, Petar Pantic, Ryan Kuchel, Letterio Silvestri, Luigi Vitale and Charlie Kambouris

After her cause of death was initially determined to be a heart attack, they properly autopsied the body after being transferred from the ship to Sydney, NSW. The autopsy then determined that a mixture of alcohol and a drug called GHB was what killed Dianne Brimble. 

GHB is a dangerous and very unpredictable party drug. It can produce feelings of euphoria, relaxation and sociability, however the instability of the drug makes it exceedingly easy to overdose with, especially when mixed with alcohol. 

While being known as ‘liquid ecstasy’, GHB is also a well-known date rape drug because it can incapacitate the user with drowsiness, amnesia and impaired movement and speech. 

When overdosed, the drug can cause unconsciousness and complete respiratory collapse, which is what happened to Dianne. 

Dianne had been married to a man called Mark Brimble with whom she shared two sons. After a few years, they split, and she started a long-term relationship with a man called David Mitchell. The pair stayed together for longer than her first marriage and she had a daughter with him, Tahlia, the same daughter who was 12-years old when she went on board the cruise with her mother. 

Dianne and David had broken up shortly before the cruise, but remained in touch and he, alongside her first husband, would be a huge advocate for her ‘character’ in the years to come. 

Mark Wilhelm never went on the stand during his trial or at the inquest that opened after, however his version of events were pieced together through tapped phone calls between himself and other members of 'The Adelaide Eight.' 

Over these phone calls, it became clear that the group were most concerned with the drug charges they were in danger of receiving. The friends corroborated each other's stories, making sure they were all on the same page with where the drugs came from and who was holding them. 

Geesche Jacobsen, author of Abandoned spoke to True Crime Conversation’s Emma Gillespie about these recorded phone calls. 

“There was never any discussion or dispute in these versions about whether it had all been consensual. That Dianne knew she was consuming a drug, and she did so willingly and knowingly.”

Jacobsen explains that while they were minimising the damage that would be taken for the drug supplying, the group, if guilty for drugging and raping Dianne, would have mentioned minimising or covering up those crimes at least once over the hundreds of phonecalls to one another, but they never did, they never felt they needed to. 

While Dianne Brimble is undoubtedly the victim in this case, they stripped her dignity from her when different versions of events from that night came out through these phone calls, portraying her in a very different light to what her friends and family knew of the 42-year-old mother of three. 

According to Mark, he had met Dianne in the nightclub where she proceeded to take him into the toilet to give him oral sex. After the club closed, Dianne allegedly asked if she could go back to his cabin with him so she didn’t have to wake up her family. 

Mark also says that sometime throughout the night several members in their party took GHB including himself and Dianne. The pair then had sex when his friends came in and took photos on their camera. 

A missing memory card from said camera was eventually found and handed in to police and on it, they corroborated this story as they found images of Mark and Dianne having intercourse. 

According to Mark, he then left with his friends whilst Dianne slept in his bed. This was presumably when she began reacting negatively to the drug, falling off the bed, defecating herself and eventually passing away.

Image: AAP

According to Mark, when they found Dianne in the state she was in they washed her body and re-clothed her and only then did they call for help. They attributed this to embarrassment and fear because they themselves had taken drugs. However, these acts can also be the sign of guilt and perhaps if they had called medical help that early, Dianne may be alive today. 

Mark's version of events didn’t sit well with Dianne’s family and her past partners. They denied Dianne would willingly have taken such drugs on a family trip where her young daughter was close by. Dianne’s ex-husband Mark and ex-partner David both adamant that the Dianne they knew would never preposition a stranger into oral sex in a public bathroom, and state that if she was in such a state of mind to be having sex in a room with strangers, allowing them to photograph her, she was not in a state of mind to be giving consent. 

However, there was no evidence that Dianne had been drugged and raped. 

While there was no evidence that she HADN’T consented, there was also no hard evidence that she had. 

Forensics couldn’t determine the amount of GHB in Dianne’s symptom as the body continues to create it after death, they also couldn’t determine whether it had been slipped in her drink or taken in another way. 

According to Jacobsen, in the years since her death, several guests from the boat now claim they heard noises coming out of Mark’s cabin that sounded like a woman saying, 'No! I’m not like that.'

However, when it came to identifying Dianne’s voice, none of these witnesses could and therefore this evidence could not be used. 

Mark Wilhelm was initially charged with drug supply and manslaughter. The judge deemed Mark responsible for Dianne’s death through negligence. 

First, for not calling for medical help when she was first seen struggling, second for providing the drugs that led to her demise. 

However the manslaughter charge was eventually dropped as they could not prove negligence when they didn’t have evidence that the men were even aware that Dianne was struggling, and that her cause of death was a combination of alcohol and GHB not just the drug. 

Ultimately, Mark Wilhelm and two other friends were only charged with drug supply and concealment, however none of them spent any time in jail. 

Dianne’s death caused a lot of cruises emergency policies to be reassessed in order to create a safer environment for their guests. 

Her family feel that to this day, justice has not been served. 

Feature Image: AAP.