Paula Bennett is accusing Winston Peters of dirty politics, saying he should be sacked as Deputy Prime Minister.
It follows the covert filming and photos taken of journalists as they met with a former NZ First president.
And the Prime Minister wants nothing to do with any of it.
They are Parliament's ultimate enemies - and now Bennett's going in for the kill.
"I do not believe he should be in the role of Deputy Prime Minister," she says.
Bennett is calling for the scalp of Peters - and trying to take the Prime Minister down with him.
"By Jacinda Ardern choosing a 'see no evil, hear no evil' approach she is supporting this kind of unethical behaviour," she says.
The behaviour she's referring to is the unauthorised, stalky video and photographs of a former NZ First president meeting journalists who broke details of the NZ First Foundation donations.
Covert pictures Peters was initially quick to take credit for.
"We took the photograph," he told Magic Talk host Peter Williams.
But later he backtracked on Twitter, however. He tweeted: "[NZ First] has no interest in following Mr Espiner or any other journalists."
"The very reverse applies. No private investigators have been engaged to follow Mr Espiner or anyone else. A supporter thought it odd seeing ex-president Lester Grey with Mr Espiner so took a photo. Simple."
Ardern says she hasn't discussed this with Peters directly.
"I did not consider it a matter that needed to be discussed," she said at a media stand-up.
But Bennett disagrees.
"It feels threatening, it feels like it is a threat to all of you," she says.
"Do journalists now have to be concerned that if they write a story against Winston Peters and NZ First, that they may be followed, they may be photographed and their source may end up on a political blog."
The photos were made public on a website called BFD - the successor to the Whale Oil blog run by Cameron Slater whose hacked emails formed the basis of the Dirty Politics book and scandal prominent in the 2014 election.
According to Ardern, she has a "distaste" for the use of "particular blogs" within NZ that she sees as "adding nothing to the New Zealand political landscape".
"If one was defining dirty politics then right now NZ First and Winston Peters would be at the top of that," Bennett says.
And the Prime Minister's choosing not to be on top of any of it. The Cabinet manual - the ministerial handbook - is crystal-clear. Ministers are expected to uphold the highest ethical standards and they're accountable to the Prime Minister for their behaviour.
Instead, Ardern is choosing to do absolutely nothing which speaks volumes about the power Peters has in this Government and how little power Ardern has over him.