Sydney, July 1960. Eight-year-old Graeme Thorne disappears while waiting for a lift to school in Bondi. His family are ordinary — a travelling salesman, his wife, and their two children, living in a rented duplex. Three weeks earlier, however, Bazil Thorne had won £100,000 in the Opera House Lottery — and the media published their names and home address.

Police have unearthed a total of seven bodies when they conclude their search at Belanglo State Forest. Attention now turns away from the forest and toward finding who is responsible. Thanks to Paul Onions, a survivor of an earlier attack in the same forest, Task Force Air gets its breakthrough. On the 5th of May 1994, police fly Paul to Australia and show him a series of images. He identifies the man he says attacked him. His name is Ivan Milat.

Police have just uncovered a fifth body in Belanglo State Forest. The victims span years of disappearances but a pattern is appearing; they all vanished while hitchhiking along the hume highway. Task Force Air has been formed to coordinate the investigation, bringing together missing-persons cases, forensic evidence, and search operations. What remains unclear is whether the forest has revealed everything it contains.

For decades, the road between Sydney and Melbourne has been a trusted passage — a route taken by families, freight drivers, and young travellers chasing work or experience. In the late 1980s, hitchhiking along this corridor is common and unremarkable. But when multiple travellers vanish without witnesses, a forest just off the highway begins to emerge as something more than a place on the map.

In Kings Cross during the summer of 1975, the Savoy Hotel is one of many old boarding houses offering cheap beds to those with nowhere else to go. But on Christmas morning, neighbours look up to see residents trapped behind windows and smoke pouring from the stairwell. What first appears to be a tragic accident will soon expose a far darker origin.

In 1977 Collingwood was a dense, close-quartered neighbourhood in Melbourne's inner-north. Its narrow terraces lived in by factory workers, students, artists and independent women carving out their own lives in the inner city. On Easey Street, two such women share a small terrace, but in January the home sits unusually still for days, with only the faint cries of a child breaking the silence. What begins as a simple welfare check quickly turns into a case that will haunt Melbourne for decades.

Warning: This episode contains descriptions of child murder.

In 1892, Sydney was a city balancing progress and poverty. Thanks to social stigma and economic hardship, unwanted pregnancies were growing and as a result “baby farming” began to quietly thrive in backstreets and rented terraces. When workmen uncovered the tiny remains of infants buried beneath a particular house in Macdonaldtown, the discovery unravelled a web of deceit that stretched across the city, exposing a hidden trade built on desperation and betrayal.

Warning: This episode contains descriptions of child sexual assault and murder.

Mr Cruel has been keeping Melbourne’s North-East suburbs in a tight grip of fear. This is now his third confirmed home invasion and second kidnaping, with no sign of his attacks slowing. His awareness of forensics makes the police investigation near impossible, but with building pressure from the public, Victoria Police will go on to form one of the largest manhunt's in Australia's history.