It is possibly the strangest ever episode of Deal or No Deal. There is no Andrew O'Keefe, golden briefcases or models wearing identical wigs.

Instead, the stars are Scott Morrison and Jacqui Lambie, and they're talking about refugees in Papua New Guinea and Nauru.

The Tasmanian senator on Wednesday voted for the medevac repeal bill, delivering the final crossbench vote the Government needed.

Senator Lambie had been demanding an agreement with the Coalition in return for backing the legislation, but no one knows the terms of the agreement.

Now neither side is daring to utter the word "deal".

So, what on earth is going on behind the scenes?

Jacqui Lambie became emotional as she confirmed her support for the repeal of medevac. ( ABC News: Mark Moore )

What's the 'secret deal' everyone's talking about?

Labor and the Greens accused the Government and Senator Lambie of striking a secret deal to end the medevac laws, after Lambie refused to disclose any details of negotiations with the Coalition.

Both the Government and Lambie have denied that any 'secret deal' took place, and the Government insisted it won Senator Lambie's support for its medevac repeal bill by providing her with classified briefings.

Finance Minister Mathias Cormann said a proposal put forward by Senator Lambie to work with the Government on the issue doesn't mean an agreement was reached.

"A proposal is not a deal," he said.

"It is a matter of public record that of course Senator Lambie put various issues to us and in response we provided detailed briefings, detailed information, classified briefings about the Government's policies on border protection, on resettlement."

Labor senator Penny Wong during the medevac repeal debate in the Senate. ( ABC News: Mark Moore )

Labor and the Greens demanded the terms of any deal be made public before the Senate voted to overturn the laws, but Senator Lambie said the lack of info was due to national security concerns.

"I know that's frustrating to people and I get that," Senator Lambie said in Parliament yesterday.

"I don't like holding things back like this. But when I say I can't discuss it publicly due to national security concerns, I am being 100 per cent honest to you."

Labor's Penny Wong told the Senate yesterday that the secrecy resulted in an ill-informed vote.

"At the moment we have cabinet ministers like lemmings coming in here to vote for a bill on a deal you haven't seen," she said.

"What sort of cabinet government is that? What sort of process of democracy is that?"

Medevac is gone — is it being replaced by permanent transfers?

February's now-scrapped medical evacuation law made it easier for those held offshore to get to Australia to receive healthcare.

Senator Lambie's proposal that she put to the Morrison Government was intended to secure her support for the repeal laws, but it's not known under what conditions.

"And since then, we have worked together really hard to advance that proposal," she said ahead of the vote.

Speculation is rife that Senator Lambie has demanded — successfully — the Government accepts New Zealand's longstanding offer to take 150 refugees each year.

Could Scott Morrison be about to accept Jacinda Ardern's refugee offer? ( AAP: David Rowland )

That is absolutely possible under the construction of words the Prime Minister chose when addressing the issue.

"The only undertaking we've given is to implement our policies," he said.

"The Government's policy is to ensure that we seek to resettle people who are on Nauru."

The Government would say its policy is to achieve third-country resettlements.

It established such a deal with Cambodia — although only a handful of refugees travelled to the impoverished South-East Asian country.

Malcolm Turnbull convinced Donald Trump to honour the Obama-era refugee deal. ( AP: Pablo Martinez Monsivais )

Then, Malcolm Turnbull's administration struck (and maintained) an agreement with the United States.

This arrangement is rehousing most of those held offshore. Home Affairs Minister Peter Dutton said 654 people had already been transferred there and 251 refugees had been provisionally approved.

And, crucially, the Government has left open the possibility of saying "deal" to New Zealand for those rejected by the US (or refusing to go).

The Coalition has previously hinted it could accept the offer if Parliament banned the cohort from ever travelling to Australia.

So, if Senator Lambie has been given enough hints that the "Government's policy" of third-country resettlement is continuing — and might be about to continue a bit faster — that may have been enough to secure her vote.

'No undertakings' doesn't mean nothing is afoot

Another (less likely) option is that the Government has not officially, formally, and finally agreed to Senator Lambie's proposal, but intends to fulfil her request.

"My understanding is that she put forward a proposal; there is no deal per se," backbench Government senator Amanda Stoker said.

"I suspect once her proposal has been considered there will be some clarity on that."

Even if policy change is likely, the Government can say (as Mr Cormann did): "We did not provide any undertakings."

Either way, both the Coalition and Senator Lambie seem to be claiming victory.

Viewers just have to wait a few more episodes to peek inside the briefcase.

But if the bag is empty, there'll be one cross crossbencher and the next season of this show will be exploding with drama.