Police say McGannan liaised with a Mexican drug runner David Negrete Nevarez who smuggled cocaine to his contacts in New Zealand.
The 3kg of cocaine seized was hidden in Nevarez's suitcase when he landed at Auckland Airport on a Lan Chile flight from Santiago in December.
The 43-year-old has pleaded guilty to importing and possession for supply of the Class A drug, and was sentenced to seven years in prison.
Justice Priestly said Gemmell was asked to collect a sample of the drug from a hotel room before taking the suitcase. Kemp was the next courier in the chain and met Gemmell in a Mission Bay carpark.
Kemp was offered money to transport the drugs but refused to take any payment on two occasions. He handed the package on to Brendan Clarke in Wellington.
According to police, Clarke agreed to find buyers for the cocaine, which was 80 per cent pure, after the original purchaser pulled out.
Police swooped when the Wellington man opened the suitcase to inspect the package.
The 37-year-old pleaded guilty to possession for supply, and will spend four years and eight months in prison.
In sentencing Gemmell and Kemp today, Justice Priestly said he took time off their sentences for the early guilty pleas, their remorse and previously clean criminal records.
"I am weaving into the sentence considerations of mercy to the extent that I am able."
He gave an extra discount for Gemmell, who had suffered mental health issues while being locked up on remand.