Like compartments on a submarine in distress, state borders in Australia are closing down to curb the spread of Covid-19.
Alarmed at a surge in infections, Queensland has already banned almost all residents from Victoria.
It will do the same for people from the national capital, Canberra, and New South Wales, which it has declared a coronavirus hotspot.
The government in New South Wales is imposing tough restrictions of its own. Travellers from Victoria will only be allowed into the state if they fly to Sydney, and go into mandatory isolation at a hotel for 14 days.