Three years ago, Britain had a new Prime Minister and a promise to take the United Kingdom out of the European Union by delivering on the people's vote for "Brexit".

What had been presented as a simple proposition - for the UK to leave - has turned into a political nightmare, dividing former allies, British political parties and the people of an increasingly dis-United Kingdom.

Now Britain's new PM, Boris Johnson, is making bold promises to "leave".

In this revealing account, key negotiators and politicians on both sides of the Channel tell the inside story of the Brexit debacle.

For 20 years the nation's city skylines have been changing with the building of more than 650,000 apartments across the country.

Glossy advertising has wooed buyers away from the traditional Aussie dream of a house with promises of sophisticated apartment living and high-end finishes. But the shine has well and truly come off the apartment property boom.

On Monday Four Corners investigates Australia's apartment building crisis, from shoddy workmanship to lax laws, leaving owners out of pocket and in some cases out of a home altogether.