Police had arrested the 63-year-old man for the triple murder at Spear Creek more than 40 years ago, after he stepped off a plane from Goulburn, NSW on Friday.

He has been remanded in custody for a committal handover on May 20.

The court, which sits next to the Brisbane Watchhouse, held no supporters, only journalists.

One woman, claiming to be the former sister-in-law of Mr Preston was waiting outside the courthouse hoping to catch a glimpse of the murder accused.

Mr Preston, a former prison guard, did not appear in court on Saturday morning after spending his first night in jail.

His lawyer had not seen Mr Preston on the morning of his court date, but said he would be fighting the charges.

Mr Preston, then an unemployed diesel mechanic, was a suspect early on in the investigation, having been convicted and fined for stealing one of the victim's motorcycles in 1978.

More than 40 years later, detectives now believe he shot Karen Edwards, 23, Tim Thomson, 31, and Gordon Twaddle, 21 in the head at close range with a .22 calibre rifle and stripped them of identification.

The trio were found slain in the long grass at Spear Creek near Mount Isa in October 197, weeks after their killings. 

Police say Mr Preston knew all three of his alleged victims.

A full police review of the cold case began after an anniversary feature into the murders was published in the The North West Star in 2018.

The feature produced fresh leads for detectives and encouraged 50 fresh witnesses to come forward.

Courtesy of Brisbane Times.