With a true story behind it, The Death Ray Debacle is set in New Zealand in the 1930's.
From the Blurb:
In June 1935 Takapuna inventor Victor Penny was attacked by foreign agents seeking what the newspapers dubbed a ‘death ray’. The government secretly shifted him to Somes Island in Wellington harbour to develop the weapon. The novel of this true story is told by Temporary Acting Detective Dan Delaney, seconded to Special Branch, forerunner of the Security Intelligence Service.