Elspeth Kerr was a prominent nurse in the Auckland suburb of Devonport in the 1930s and faced three trials over the poisoning of her foster daughter Betty.
Betty lived, but as police investigated they found cause to exhume the bodies of her husband Charles - who had died just a few months before Betty became sick - and another patient called Emma Day. At the time, the case was sensational, but over time was lost to history - until a skeleton was unearthed under a Devonport house in 1992.
Investigative author Scott Bainbridge has written The Trials of Nurse Kerr: The anatomy of a secret poisoner. It's his ninth book, he's also written Without a Trace and Still Missing. Nine to Noon last spoke to him about his book The Fix, which looked at one of New Zealand's biggest swindles.
