Osman El-Houli told police a man called The Professor hired him for $10,000 to drive almost 3000km and collect bags of cash.
However, El-Houli may have been tricked by a syndicate aiming to pick up $141 million worth of drugs from a plane arriving from Papua New Guinea, his defence barrister says.
El-Houli, 35, has been accused of driving his truck from Melbourne to collect more than 400kg of pure cocaine in far north Queensland in July 2020.
The drugs never arrived after a plane bound for Mareeba crashed attempting to take off at a remote PNG air strip, the Crown says.
It is believed the operation was run by a syndicate consisting of a Colombian group and Melbourne mafia, a Brisbane Supreme Court jury was told.
Defence barrister Tony Kimmins said the courier for a prior "black flight" from PNG was in custody in July 2020.
He suggested the syndicate hired a "dupe" courier in 2020, a cleanskin who would not raise suspicion at COVID-restricted border controls.
"One of the cogs in the syndicate who were able to pull off the first importation was no longer available," Mr Kimmins told the jury on Thursday.
"Consider this for a moment ... about a dupe, getting someone to basically occupy the role that had been previously occupied by a syndicate member."
He added: "Who was brought in to occupy that very serious position - a simple man who owned his own truck...no problems with the law.
"You might just stop and think he (El-Houli) was brought in because of his good background."
El-Houli was arrested after police found his truck parked near Mareeba on the day the plane crashed.
He told police he had been hired for "a lousy $10,000" by someone called The Professor to drop off plasterboard in Queensland, the court heard.
However, he said en route he was told there were concealments in the plasterboard and he would be picking up bags of cash and returning to Melbourne instead.
El-Houli did not know The Professor well, the court heard.
However Mr Kimmins said The Professor was an international drug smuggler in his own right and a "confidence trickster".
El-Houli was a devout Muslim of good character who hated drugs and would not "sell his soul" to be a cocaine courier, he said.
Crown prosecutor Daniel Caruana asked the jury not to be distracted by the "smoke and mirrors" surrounding the syndicate co-conspirators.
"In some respects you might even think it is pretty exciting, this big Hollywood conspiracy," he said.
"Don't get carried away with all the excitement around the co-conspirators or the fact that there are some other serious customers involved."
He said El-Houli would have known "deep down" that drugs were involved after being given an encrypted phone for an interstate trip transporting bags in concealments.
"What do you think you could possibly be collecting ... you are being asked to collect drugs," he said.
El-Houli has pleaded not guilty to attempting to possess an unlawfully imported border-controlled drug.