The tram stopped and we stepped out into chaos.
I'd been on my way to the Australian Open on a mild summer's day when it was held up at the Elizabeth and Bourke streets intersection.
The driver told passengers a "police incident" had delayed the tram, and some of us got off.
The chilling screams of police officers filled the air outside.
Some ordered the public out of the way, another yelled to a colleague holding the keys to a police car making up a hastily arranged blockade.
In the next breath, a messy stream of blue and white cars sped up Bourke Street chasing something we couldn't see.
A visibly frightened middle-aged man told me: "A car just sped up the footpath."
His eyes were fixed on a stretch of footpath where three people lay motionless.
One woman was face down.
Many people who'd luckily avoided being hit did what they could to help. Some attended to wounds, others comforted the injured, others blocked out the summer sun with umbrellas.
A dismayed woman inside a shop recalled the moment the car passed her.
"It was going at about 60km/h, and just went boom."
You could trace the car's path up Bourke Street by the startled faces, the heavily armed police and those tending to the victims.
Two police - clad in bullet-proof vests - attended to someone in a gutter as a colleague performed CPR outside a newsagency.
A lone white running shoe stood in the centre of the footpath, next to an upright and battered bumper bar broken off in the carnage.
Small clusters of injured appeared every hundred metres.
At the pedestrian crossing of William and Bourke Street lay the mangled, empty wreck of a baby's pram.
As they'd done elsewhere along Bourke Street, startled crowds gathered behind police tape as police and reporters zig-zagged in between trying to piece it all together.
But even hours after the bystanders dispersed and the final ambulance victim departed, Melbourne didn't return to normal.
With many workplaces closing early and much of the CBD segmented by police tape, the city centre was mute at 5pm.
The chaos had turned to eerie silence.
