27/09/2016 9:04 AM AEST | Updated 27/09/2016 9:07 AM AEST

How Detectives Caught Jill Meagher's Killer, Adrian Bayley

'Conviction', a documentary on the case, airs on ABC tonight.

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The shocking and brutal murder of Melbourne journalist Jill Meagher captivated the nation in 2012, and will be revisited in a new documentary to air on the ABC on Tuesday.

'Conviction' reopens the book on Meagher and her killer, serial sex offender Adrian Bayley, four years after the September 2012 murder and rape. The detectives in charge of the case will speak openly about their investigation, giving new insight into how they caught Bayley.

The case quickly took hold of Australia when it emerged, after Meagher disappeared after leaving a bar to walk home. Six days later, Bayley -- who was out on parole at the time, and had previously been convicted of a string of violent sexual assaults -- confessed to strangling her, then led police to where he had buried her, 50 kilometres outside Melbourne.

On the short walk from the pub back to her home, Meagher had briefly encountered Bayley on the street. CCTV footage from a boutique captured their short meeting, and Bayley later killed her.

Bayley's court trial was intensely reported by media, as he was eventually sentenced to life in prison.

Fairfax Media via Getty Images
Tens of thousands of people walk along Sydney Road in Brunswick, Melbourne, in a peace march to commemorate murdered Irish woman, Jill Meagher, on September 30 2012.

"This is not the first time that you have been found guilty of violent sexual offences," the judge said.

"As your criminal record reveals, you are a recidivist violent sexual offender who has had little compunction about sexual offending when the mood takes you, or about threatening and inflicting violence as part of the process."

In the documentary, police talk about their initial focus on Meagher's husband, Tom, as a possible suspect.

"When you think about it down the track, you're left thinking 'Jeez, we were pretty awful, for the way we've treated this poor guy'," said Sergeant David Butler.

Conviction premieres Tuesday 27th September at 8.30pm on ABC.