Geoff Parton delivers a gripping, atmospheric tale, where a single arm from a shark's belly would unravel an entire web of lies. What follows is a murder mystery like no other. A twisting journey through Sydney's glittering surface and its dark underbelly of crime, deceit, and corruption. Cold Case Murders: Sydney, 1930s unearths a chilling story behind a most bizarre and sensational crime. Who did the arm belong to? Who cut it off - and why? As secrets emerge from the harbour depths, respectable men are revealed as dangerous criminals, and the line between high society and the criminal underworld begins to blur. One shark. One arm. A trail of secrets that refused to sink.