Inside a dangerous terror network in Australia — the man who infiltrated it speaks out.

One year after the Wakeley church stabbing shocked Australia, a former secret agent who infiltrated the country's jihadist underworld unmasks himself.

In an extraordinary Four Corners exclusive, the former ASIO agent reveals to investigative reporter Sean Rubinsztein-Dunlop how a resurgent Islamic State (IS) network is radicalising Australian teens and plotting violence.

He exposes the network's links to a global web of terrorist leaders.

The agent spent years inside extremist circles, helping authorities thwart attacks and stop IS terrorists.

Now, with teenage terrorism and hate crimes on the rise in Australia and around the world, he's stepping out of the shadows to sound the alarm.

Over summer, organised crime cast a terrifying shadow over Australia.

The Jewish community in Sydney was left reeling — shaken by a wave of attacks that culminated in the discovery of a caravan packed with explosives and a list of Jewish sites.

NSW police have maintained that the crimes are connected, that a mastermind has orchestrated more than a dozen attacks.

In the months following the caravan's discovery, a name began to emerge: Sayit Erhan Akca—a figure well-known in Sydney's criminal underworld, currently on the run from Australian authorities.

Reporter Mahmood Fazal travels to the country where Akca is hiding to seek answers about his involvement and to challenge his account, in the hope of piecing together the truth of what really happened.

In his first ever TV interview Akca makes stunning admissions, raising questions about how authorities have responded to this unprecedented wave of crime and hatred.