In Australia, there are over 40,000 men and women currently behind bars. Many of them have done very bad things. They have shattered countless lives, destroyed families and been responsible for unspeakable criminal acts.What did they do? How did they get here? And what are their lives like now?This new series, Australia's Most Dangerous Prisoners, will outline in detail the crimes that landed these men and women in Australia's high-security jails through first-hand accounts by ex-inmates, former correctional officers, journalists and forensic psychologists, who try to make sense of their world.