A man involved in a "bizarre and quite ridiculous" plot to provide some muscle to secure the return of opals stolen from a Kangaroo Island sheep shearer has been jailed for just over three years.
Mark Anthony Villani pleaded guilty to a string of charges including two counts of aggravated theft, and firearms offences.
Sentencing the 34-year-old in the District Court, Judge Stephen McEwen said he was recruited by a woman who claimed to have had a valuable opal collection stolen and who was unhappy with the police investigation.
He said the woman suspected she knew who was involved in the theft and recruited Villani and another man to travel to Kangaroo Island and provide her with some sort of assistance "along the lines of threatening and intimidatory behaviour".
"If that all sounds strange and ridiculous that is because that is what it was," the judge said
When the men arrived on Kangaroo Island they had a meeting with the woman, discussing some "vague plans or instructions".
The two men then went off before returning with a tablet and some fairly worthless plastic jewellery.
But then they turned their attention on the woman, stealing a range of property including a phone, smartwatch, laptop, handbag, cash and her car.
Villani also produced a shotgun loaded with blanks which he fired near the woman's head in a bid to convince her to sign over the car's registration papers.
Judge McEwen said Villani had suffered a violent and traumatic upbringing, with his father murdered when was just four.
That killing remains unsolved.
But he said Villani also had a long history of offending and had been "slow to get the message" that offences involving firearms were serious.
The judge jailed him for just over three years and two months and set a non-parole period of 22 months.