The Government had admitted it has no idea where the lethal strains of so-called synthetic cannabis are coming from.
Eight people have died in recent weeks after using the illegal substances, which were driven underground with the introduction of the Psychoactive Substances Act in 2013.
"We don't have any idea whether this is a batch being supplied from overseas, or whether it's materials being concocted together in New Zealand," Peter Dunne, the MP behind the legislation, told The AM Show on Thursday.
"I suspect it's going to be a bit of both."
Nor is there much information out there on what's in them - in contrast to pre-2013, when they were legal and packaged like any other product.
"There are hundreds of [ingredients] potentially, and the combination of those is what's creating these very dangerous designer drugs," said Mr Dunne.
The lack of information is making it difficult to prevent the drugs reaching the streets.
The intention of the 2013 law was to create a legal passage for substances to be legalised if they were proven to be low-risk. But no licence applications have been made - there's a $180,000 fee to apply, plus testing costs likely in the millions of dollars and a ban on animal trials.
"I said this would happen if we drove this market underground and sadly that's exactly what has occurred, because we haven't been able to proceed fully with the psychoactive substances legislation," said Mr Dunne.
Death by any other name?
Mr Dunne wants the drugs rebranded, saying the stuff that's killing people in the streets is nothing like the real thing.
"The term synthetic cannabis is a misnomer - this is a psychoactive mix of a range of substances. It's not just cannabis substitutes," he said.
A former addict wrote to The AM Show, suggesting the media start referring to the drug as 'Death', saying no one would even start smoking a product by that name.
Legalisation, or full Duterte?
The deaths have sparked much debate on how to tackle the growing problem. Pro-cannabis advocates say if the real thing was legal, no one would be tempted to try synthetics.
AM Show newsreader Amanda Gillies said in all her years of court reporting, she "can't recall an incident in court that was caused by smoking marijuana".
Host Duncan Garner said treating it as a health issue is paramount, but sports newsreader Mark Richardson had another idea.
"Hit it at both ends as hard as you can. At the health end, for people who are addicted, give them the help they need; and get stuck in to those people that we know supply it. Take their civil rights from them because we know who they are.
"Bugger them. Don't protect them, and rid this country of them."
Mr Dunne's temporary solution is to just say no.
"Don't use these substances. I can't put it any more bluntly than that. They are lethal, they will kill you."