In the aftermath of the attack in the Bourke Street Mall, two men cared for a woman hit by the maroon car that senselessly mowed down pedestrians on Friday.
As his hand shook with fear, Melbourne man Henry Dow was calmed by someone he assumed must have been an emergency services worker.
"Lou grabbed my hand and firmly told me to keep it together, that I was OK and that we needed to keep strong for this woman," Mr Dow recalls.
'Lou' was not a paramedic. He was a taxi driver who did not hesitate even in the terrifying minutes after the attack.
In a moving letter written a day after Friday's attack, Mr Dow acknowledges Lou and the other unsung heroes of Friday's attack - and pays tribute to the city he loves.
This is what he wrote:
"This moment already feels surreal; without the sounds of violence, rush of adrenaline and smell of fear the photo doesn't look real. The images playing in my head are more vivid and more colourful. This image looks so orderly; no rushing, no shaking hand and quivering voice, no screams, crashes or bangs.
I write this not for sympathy (I'm fine); I just wanted to share a story that otherwise might be lost.
Administering first aid with me, under that skinny little tree, is a man named Lou: he is everything great and courageous you have seen, heard or read, rolled into one authentically humble bloke.
Having seen the car fly past, my legs carried me across the street almost on auto-pilot, swearing under my breath repeatedly as it sunk in what had just happened. Some basic Surf Life Saving training got me through the first stages of helping this poor woman: roll her on her side, support her neck, we talked kindly and as calmly as we could to her.
Then the gunshots.
Holding her head, my hand was, for want of a better word, shaking. It was more like bouncing, moving several inches up and down as the fear and thoughts of what had happened, what could happen, raced through my head.
Lou grabbed my hand and firmly told me to keep it together, that I was OK and that we needed to keep strong for this woman.
In a level and loud voice, Lou barked orders at other pedestrians standing by, having not fled, but still too stunned to think or move.
He directed assistance to several of the victims laying on the pavement around us, all whilst keeping me calm and speaking lovingly to this woman: "I am Lou, you are going to be ok, we are looking after you".
It kept going through my head, "thank f**k I lucked out and have an emergency services veteran here with me". Surely Lou was ambulance, police or SAS. Lou was not.
Lou, in his white shirt and neat dark tie, was a taxi driver.
In our small story, of this much bigger tragedy, Lou took command and was a genuine hero.
We have all seen images and opinions flood the media over the past 24 hours. If you feel like shaking your head and feeling sad for the state of humanity, I implore you: Don't.
There was no evil on Bourke Street yesterday; one sick young man did a terrible thing, and hundreds responded with the love and sense of community that makes Melbourne such a beautiful city, and Victoria such a great state.
There was only kindness in the voices of the police who came to relieve us.
I felt only love when an older man hugged me, having just told a father he had lost a daughter.
Many images and sounds will stay with me much longer than I might like, but I am glad to have seen, and hope I never forget, just how brave and loving strangers can be.
Daniel Andrews, our capital city owes a great debt of gratitude to Lou for what he did yesterday.
I love this city."
Donations for the immediate families of those killed can be made via the website www.vic.gov.au/bourkestreet.html
A vigil is being planned from 5.30pm on Monday at Federation Square.