Australian cases of partners in murder: true cases of pairs of killers who act in concert and commit the most horrifying crimes. One of the most mystifying aspects of contemporary murder is the emergence of pairs of killers who act in concert and commit the most horrifying crimes. Pairs of killers have always operated together in gangland-style killings but what motivates people who, in many cases, are extremely intelligent and apparently socially stable to form a duo to kill for pleasure? In all, 11 cases, diverse in nature but equally chilling, are profiled. Many of these cases have current relevance either because the killers are seeking parole or because of what has happened to the victim's relatives or the murderers themselves.