She made it home. The Christmas card she'd gone out to buy was still on the kitchen table when her mother arrived that afternoon. Rhianna wasn't there — and she hasn't been seen since.
A Snap Bus Strike, and a Change of Plans
On the morning of October 7, 1992, twelve-year-old Rhianna Barreau was home alone in the family house on Wakefield Avenue, Morphett Vale, a suburb south of Adelaide. Her mother Paula had left for work at around 8:30 a.m., and her brother Shannon was away on school camp. Rhianna was on school holidays.
The original plan had been for Rhianna to catch a bus to the Colonnades Shopping Centre, about six kilometres away, to meet her mother for lunch and buy a Christmas card for her American pen pal. When a snap bus strike was announced that morning, Paula suggested Rhianna walk instead to the closer Reynella shopping centre — about 1.5 kilometres away, a roughly twenty-minute walk through their residential area.
Paula kissed her daughter goodbye. It was the last time she saw her.
What the Day Looked Like
Rhianna appears to have stayed home until mid-morning. At 10:30 a.m., she was spotted walking toward the Reynella newsagency. At 11:19 a.m., she purchased a Christmas card from the newsagency. Witnesses placed her at 12:30 p.m. on Highway Drive, near Morphett Vale High School, walking in the direction of her home.
She made it back. The Christmas card she'd bought was found on the dining room table when Paula arrived home around 4:10 p.m. The television was on. Records were scattered on the lounge room floor. Her personal belongings were all in the house. The front door was unlocked but there was no sign of a struggle, no sign of forced entry, no physical evidence of any kind.
Rhianna was not there.
A Massive Investigation That Found Nothing
The case rapidly became one of the largest investigations in South Australian police history. Within weeks, more than 1,600 calls had been logged. Officers worked systematically through the community, deployed cadaver dogs, searched waterways with divers, and organized volunteer searches across the surrounding suburbs. A mannequin was dressed in Rhianna's exact outfit and displayed in shopping centres to help witnesses recall their memories. Every tip was followed up.
Nothing led anywhere. No trace of Rhianna — not remains, not clothing, not any physical evidence — has ever been found.
One potentially significant lead involved witnesses who reported seeing a white LH Torana sedan with a black spoiler, reportedly carrying Victorian licence plates, parked near the Stanvac Kindergarten on the day Rhianna disappeared. The car was never identified or located.
What Police Believe
South Australia Police have described this case as one of the largest files held by their major crime unit. They have formally stated their belief that Rhianna was abducted and murdered, and that the offender is likely someone who was living in or connected to the Morphett Vale area at the time.
No suspect has ever been publicly named. Detectives have described several persons of interest over the years, including, at various points, people known to have been in the area with histories of offending against children. In the early 2010s, investigators approached Rhianna's relatives to revisit who they believed may have been involved — though police subsequently clarified this was part of ongoing review, not a formal re-investigation.
The lead detective from the original investigation said in 2020 that he still believes the answer lies with someone who was close to the neighbourhood: "Without assistance from the community this case will flounder and may become another mystery that we may never solve."
A $1 Million Reward
The reward for information leading to a resolution in Rhianna's case has grown to $1 million — one of the largest active rewards in Australian missing persons history. It remains unclaimed after more than 30 years.
Rhianna would be in her mid-forties today. If you have any information about her disappearance, you're urged to contact Crime Stoppers South Australia on 1800 333 000.
Sources
Disappearance of Rhianna Barreau — Wikipedia
Rhianna Barreau — Australian Federal Police National Missing Persons