But Jake Bilardi wasn’t just calling to confirm what his family feared the most: that he had flown to the other side of the world to join Islamic State.

The 18-year-old was calling because he thought it was his last chance to speak to his brother.

“I signed up for a martyrdom operation,” Jake told Chris.

“I’m going today.”

FROM TEEN TO A TERRORIST

It was the story that shocked Australia. Jake Bilardi, a pale teenager from Melbourne’s northern suburbs, had joined the Islamic State death cult and blown himself up in Iraq.

But it is only now, more than seven years later, that a News Corp investigation can reveal the inside story of how Bilardi was radicalised in his bedroom and died on the battlefield.

At the centre of it is Mirsad Kandic, an evil Islamic State mastermind who smuggled the teenager into Syria and encouraged his suicide bombing.

Kandic’s extraordinary trial in a US court – where he has been convicted of serious terrorism offences including causing Bilardi’s death – has shed new light on the final months of the teenager’s life.

Bilardi first came across the recruiter a fortnight before his 18th birthday in 2014, sending a Twitter message to Kandic that would change and ultimately end his life.

For months, Bilardi had been intently researching Islamic State. He watched videos on his government-issued laptop such as “There is No Life Without Jihad”, which featured English-speaking fighters including Melbourne’s Neil Prakash. And he devoured the books on his shelves: The Meaning of the Holy Quran, Inside the Jihad, The Roots of Terrorism.

In his bedroom in a red brick Craigieburn house, the soccer fan was no longer interested in his other books on his childhood heroes Cristiano Ronaldo, Lionel Messi and Diego Maradona. Bilardi’s Nintendo Game Boy Advance was stored away, as was his red tartan pencil case – owned by just about every child of the 1990s – after he dropped out of school.

All of Bilardi’s attention was on joining Islamic State – but he faced “one key roadblock”.

“How was I to get in? I had no contacts to assist me,” he later wrote on his blog.

“After failed attempts at finding a contact I gave up all hope.”

That was until he found Kandic, the man behind the Islamic State propaganda account @Dawla_NewsMedia, who bragged of smuggling thousands of foreign fighters into Syria.

Kandic told the Australian to learn as much Arabic as he could, to run every day to prepare for frontline training, to bring US dollars, and to fly to Istanbul and pretend to be a tourist.

Straight away, Bilardi put his advice into action. He ordered a Nokia phone from Dick Smith and a khaki backpack from ASOS, and exchanged $6000 for American money.

On the day his passport was issued – after he paid extra for it to be expedited – he booked a one-way flight to Istanbul via Singapore, making sure to request a Muslim meal.

In the early hours of August 25, his family none the wiser, Bilardi put on a traditional Arabic scarf and climbed into a Silver Service taxi outside his home at 5am.

CCTV cameras soon captured him checking in at Melbourne Airport and walking through the terminal to board Turkish Airlines Flight TK7925, which departed at 10.25am.

It was the first time the 18-year-old had left Australia.

Watch the never-before-seen CCTV footage below:

JAKE’S ISLAM CONVERSION

Bilardi turned to Islam around the time of his mother’s death from cancer in 2012.

It had been a traumatic period for the shy and awkward teenager, who had been living with her and his five siblings after his atheist parents divorced.

Bilardi started visiting Hume Islamic Youth Centre, half an hour away by bus in Coolaroo. That was where he took the shahada – the profession of faith required to become a Muslim.

Hume was also visited by others who became terrorists: Hassan Khalif Shire Ali, who stabbed three people on Bourke Street in 2018; Adam Dahman and Dawod Elmir, who both died fighting in the Middle East; four men who plotted to attack Melbourne landmarks on Christmas Day in 2016.

While Bilardi may have crossed paths with some of them, his computer hard drive suggested his radicalisation happened largely online. In hindsight, his family suspected it was also connected to mental health problems, for which he had seen a psychiatrist on and off.

Bilardi was bullied relentlessly at school, including over his conversion to Islam. An intelligent student, he began to withdraw from his classes and his dream of becoming a journalist, instead drifting deeper into darker circles online.

“I was growing tired of the corruption and filthiness of Australian society and yearned to live under the Islamic State,” he wrote on his blog.

With limited means to reach Syria, Bilardi turned his attention to fighting at home, drawing up what he called his “Plan B” for bomb, grenade and knife attacks in Melbourne. He bought six 500g containers of barium nitrate, a chemical compound used in homemade explosives.

Finding Kandic changed Bilardi’s mind. He hid the containers in his bedroom and plotted his escape.

A CHILLING CALL HOME

The day Bilardi first called his brother Chris from Iraq was not the day he died. But he was not deterred by his brother’s warnings.

“I don’t know what it’s achieving,” Chris pleaded with Jake in October 2014.

“It’s achieving maybe something for you, because you think that it’s benefiting you, that you go to heaven or something. But it’s not benefiting anybody else. You’re going to be killing innocent people.”

“No, no, no, no,” Jake replied.

“It’s going to be Iraqi soldiers. It’s not, they’re not innocent people.”

“I know even if I spoke to you for, you know, 20 hours that I wouldn’t be able to convince you that it’s right.”

Exclusive audio: Listen to Jake’s phone call to his brother Chris below:

When Chris told him to leave the death cult, Jake said: “There’s no way out and I don’t want a way out, to be honest.”

Bilardi and seven other suicide bombers were soon sent on a mission in the city of Baiji.

Three blew themselves up – one at a gate where there were no Iraqi soldiers – and Bilardi was next in line before the operation was called off amid constant air strikes.

On December 24, as Bilardi’s family faced the prospect of their first Christmas without him, the 18-year-old found Kandic’s new Twitter account. He told him he was now waiting for a new mission in Ramadi.

“Level these kufar with the ground,” Kandic replied.

“I’m very happy for you … We in our IS Nation are all very proud of you.”

HIS SUICIDE MISSION

Bilardi’s death wish was delayed again until March 2015.

In the days beforehand, he began tweeting publicly to try and speak once more with Kandic, whose Twitter accounts were regularly being shut down.

When they made contact, Kandic said: “You’re still breathing this worldly air.”

“Unfortunately yes, hahaha,” replied Jake, who said there was “something big” planned soon in Ramadi.

“Just really want to go on my operation, I’ve been getting told for three months that it should be only a week or so away.”

He expressed similar frustrations in a call with his brother Jesse in late February.

While Jesse said he feared Jake had already “gone on a mission” when he didn’t answer his call, Jake said there was “not really much fighting going on” as he waited for his orders.

By the time Bilardi reached Kandic, he had scouted the location of his attack, and 200 Islamic State soldiers had arrived from Syria in a bid to take control of the city.

“May Allah reward you immensely,” Kandic told him.

“May Allah make there (sic) inner organs implode.”

Five days later, the 18-year-old drove a white 4WD full of explosives down a dusty road, towards a death he told his family he hoped would “feel like the prick of a needle”.

Kandic immediately tweeted the “breaking news” to the world.