In the midst of a brutal attack, young mother Lena Kasparian picked up a knife to ward off her violent partner and protect her children.

Her attacker, Marc Zartarian – who had just used a saucepan to repeatedly beat Ms Kasparian over the head, pushed towards her yelling, “Stab me, stab me, just do it, just do it!”

He stepped forward and the knife pierced his chest by just 14 millimetres.

“14MM” airs this Sunday on Channel 9 after The Voice. For more on 60 Minutes, head to the official website.

The wound – smaller than a paper clip – was impossibly tiny for the damage it caused, missing cartilage and ribs to pierce his heart.

Marc Zartarian died and Lena Kasparian was charged with murder.

This Sunday on 60 Minutes, reporter Tara Brown investigates the tragic tale of how the tiny tip of a knife took the life of one and ruined another.

“There was no force,” Ms Kasparian told Brown.

“He was alive. He wasn't dead. There was no blood gushing anywhere, there was nothing.

“It was just a tiny little cut. Fourteen millimetres.”

With unprecedented access to Ms Kasparian’s first call to emergency services, her police interview, and her then-five-year-old daughter who saw it all – Brown takes audiences back to the awful evening and it’s chaotic aftermath.

“It does hurt when people say nasty things about you and call you a murderer when you know you’re not,” Ms Kasparian said.

On the day of Zartarian’s funeral – which Ms Kasparian wasn’t allowed to attend – she was charged with murder and told she faced up to 20 years in prison.

Immediately she was branded a calculated killer.

During and after her trial, Ms Kasparian’s story provoked more anger than sympathy with the wider community, debating whether she was truly a victim of domestic violence or a murderer.

Her stoic, unshaken appearance at court displaying a high-fashion wardrobe made outsiders question her story.

The media too joined the chorus and dubbed Ms Kasparian “Australia’s Black Widow”, suggesting she had got away with murder.

“Why do you think you were painted in that way?” Brown asked.

“Am I supposed to wail and cry like a crazy person to make people feel sorry for me?” Ms Kasparian answered.

“I'm not going to behave in a manner that I don't normally. I'm not going to be someone I'm not just to prove a point.”

What Ms Kasparian had to endure to beat her murder charge is truly astonishing. But the question audiences will this week ultimately face is: should she have faced a murder trial at all?

At what point does self-defence become murder?

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