The talks taking place between the Conservative Party and the DUP to thrash out a voting deal, place Brexit in an unusual situation. Despite a general election called in pursuit of a mandate to negotiate a 'hard Brexit' by the Prime Minister, we now find ourselves in a situation where free movement could be a necessary by-product of any deal to form a UK government.
While Leave voters in the referendum might have seen the ending of free movement as one of their key concerns, the realities now presented by the surprise general election result make this much more complex.
With the long standing history of troubles between unionists and republicans, the DUP are understandably reticent to see hard borders and check points between Northern Ireland the Republic. But not introducing a hard border would make free movement almost impossible to prevent.
A soft border between the two, could mean a soft border between the UK and the EU. Citizens would be able to travel to the Republic on EU passports and pass into the UK through Northern Ireland. At the very least it would imply continued membership of the EU Customs Union. Not quite the 'control of our borders' which Theresa May promised in April.
So for an agreement to be reached between the two parties something will have to give. Introduce a hard border and risk aggravating troubles in Northern Ireland or relax an approach to free movement which May has to date presented as 'the will of the people'.
Free movement of citizens from the European Union was one of the most discussed topics in the referendum campaign period. We heard an array of arguments and counter arguments about the impact on UK citizens, our connection to the economy, the importance of EU workers to the NHS and of course a multitude of migration statistics.
Theresa May approached the topic robustly, announcing that Britain would leave the Single Market with the ending of free movement an integral part of that process.
It's not difficult to see why she may have taken that approach. A YouGov poll in the run up to the referendum found that the public believed immigration would be better addressed with a Leave vote. And the rise in proportion of the UKIP vote was one of the major triggers for David Cameron calling the referendum in the first place - and theirs was a campaign very much wedded to the prevention of free movement from the EU.
The general election was very much the next step on this journey. An attempt to gain the mandate that would help define what Brexit is, and end opposition to withdrawal from the Single Market. But the result may have unexpectedly thrown up a very different definition. Not only did it suggest a more nuanced public view on Brexit, but the Conservatives now find themselves with an unlikely bedfellow. One for which free movement may well be a deal breaker.
So May faces a very difficult balancing act. Continue to focus on what was seen as the major issue leading to the Leave vote and end free movement - while risking scuppering a deal with the DUP. Or accept the softer approach to ensure a deal can be reached and Northern Ireland maintains a soft border with the Republic - regardless of the knock on effects.
In any event, either option could well see a breakdown of the government and a return to the polls, something that many pundits now predict could happen within months. And a buoyant Labour opposition under the new-found acceptance of Jeremy Corbyn as Leader are continuing to operate in campaign mode, having improved their standing in the electorate, particularly with young people.
It is a highly unexpected turn of events and if a Conservative-DUP alliance is reached it seems likely a softer Brexit is now on the cards. If free movement is to be a by-product of the minority government, membership of the Single Market could well follow. We now find ourselves in a situation no experts predicted. "Back to the Future" anyone? But I'm sure we've all had enough of experts by now.