Scene I: Writers' Buildings has shrunk ' the ground floor has disappeared, only the tip of the arched entrance can be seen. Laldighi, the huge waterbody in the centre of BBD Bag, too, has disappeared, as have the roads around it. A sheet of water covers the entire area from Stephen House to the General Post Office and from Writers' Buildings to Telephone Bhavan.
In the driving rain, army and navy personnel move around in speedboats, rescuing VIPs trapped in the state's administrative headquarters.
Scene II: In the normally bustling slums of Topsia and Tiljala, there's a strange silence, broken only by wails of despair. The upper floors of some buildings stick out from 10 ft of water swamping the area.
In a corner of the second floor of one of these buildings, a woman weeps inconsolably ' her two little children have been swept away.
Scene III: Forum is packed ' there's no way out. With six ft of water surrounding the island mall, cars in the underground parking lot completely submerged, cell phone networks jammed, and the authorities warning that power supply could be switched off any minute, a nightmare on Elgin Road is about to be lived out.
DATE: Any day, any monsoon
It can happen right here. The scenes of death and destruction played out in Mumbai last fortnight can visit Calcutta on any rainy day, warn city planners.
And it would not even take the 900 mm of rain recorded in pockets of Mumbai for Calcutta to go under.
'This city will drown even in 300 mm of rain,' says Calcutta Municipal Corporation's chief engineer Swapan Duttagupta. 'If it is more than that, God help the city.'
Likening Calcutta to a ship sinking in mid-ocean, Duttagupta said if it does rain more than even 500 mm, the city 'would appear to be dipping slowly from one end to the other, until finally disappearing under water'.
The first to go would be the low-lying eastern parts of the city, till the rising waters gradually devoured the entire city. The western end would be the last to drown.
If the city bordering the Arabian Sea could receive 900 mm of rain in one spell, can the city off the Bay of Bengal suffer the same'
'Such a possibility does exist,' says G.C. Debnath, director of the weather section of the regional meteorological centre in Alipore.
In 1978, 378 mm of rain submerged the entire city, bringing it to a halt for almost four days, recounts Duttagupta.
Adds Pabitra Giri, director of the Centre for Urban Economic Studies: 'But even if we receive 400 mm of rain today, the effect could be more devastating. The population has grown, the natural drainage area to the east has been clogged with buildings, and the outflow outlets have been blocked. With 900 mm of rain, the city would be doomed.'
The unplanned ' and often illegal ' constructions along EM Bypass and beyond have compounded the city's civic problems.
Once submerged, it would take seven days to two weeks for the water to recede, forewarn experts.
And the aftermath' 'There will be people dying like flies in the slums and pavements and a pestilence will break out after the waters recede,' says K.J. Nath, former director of the All-India Institute of Hygiene and Public Health.