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.

For 12 weeks Hong Kong has been convulsed by turmoil as pro-democracy flash mob protestors rise up against mainland Chinese rule. We go on the frontline to witness the escalating violence and chaos with extraordinary footage.