It was a love letter to his sweetheart that undid Frank Burns, when a wartime censor snooped into the military defaulter's correspondence.
Burns had alternately been hiding out in West Coast bush and working in the mines while evading World War I military service.
As a miner he had sought an exemption after being called up under the conscription system. He was supposed to be at Waiuta near Reefton but when they found he wasn't, the authorities began the chase.
"Damn it, you know I love you," Burns, under the false surname Lonnigan, wrote to Doll Nugent in Melbourne.
But the March 1918 letter was a double tragedy. Burns noted the rumours Nugent was now married; and by giving his address as Ngakawau, north of Westport, he unwittingly set the snare for his capture.
Censorship of mail had begun in New Zealand soon after the start of the war in 1914 and continued until 1920, two years after the hostilities ended.
Burns' letter to Nugent was opened by censors in Australia, who sent it back to the New Zealand police and army.
"They found him working at the mine in Stockton and he was arrested and jailed for resisting conscription," said Jared Davidson, who in his spare time writes history.
Davidson recounts the tale in his new book, Dead Letters: Censorship and subversion in New Zealand 1914-1920.
Jared Davidson's new book, Dead Letters
Burns' letter - and a clipping of West Coast fern he enclosed - are held in by Archives New Zealand, where Davidson is an archivist, in what was the army's "Secret Registry: Confidential Series".
Among the 500 or so items in the series are 57 letters and extracts of 17 others that were intercepted by the censors. They opened and examined nearly 1.2 million letters, postcards and packages during the war - but this was only a tiny fraction of all mail: in 1917 alone, 6 million letters were posted each week.
Davidson said the confidential series contains what were considered some of the most subversive letters opened by the censors.
Some cinema and print censorship had begun in the decades before the war, but the only personal correspondence the state had taken a real interest in was between some Māori during the New Zealand Wars. Censorship of all kinds of communications ramped up in the war, a move generally supported by the public.
"In an era when post was paramount, the wartime censorship of correspondence heralded the largest state invasion of Pākehā private life in New Zealand's history," Davidson said.
And we've never regained the age of innocence, governments remaining convinced of the value of snooping.
Defence Minister James Allen wrote to Prime Minister William Massey eight months after the war: "... a good deal of valuable information comes to the Government through the medium of the censor, and it was thought wise not to lose this information."
Censorship of private correspondence ended in 1920, but other aspects of the wartime surveillance system were continued until 1947. Also in 1920 came the birth of the police Special Branch, a forerunner of today's state spying agencies.
Domestic postal censorship began as a way of rooting out pro-German sentiments or anything that could undermine the war effort. But it soon focussed on potentially disruptive dissenters - pacifists, socialists, unionists, military defaulters, foreigners, some Māori and Irish people, and others who might be hostile to the British Empire.
Davidson said two-thirds of the detained letters held in the Secret Registry were stopped on political, anti-conscription or socialist grounds.
Who was Hjelmer von Dannevill?
The case of Hjelmer von Dannevill, who was interned briefly on Wellington's Matiu/Somes Island, was more complex. She helped run a naturopathic retreat in Miramar. Her hair was short and she wore a man's hat, coat, vest, collar and boots - and a woman's skirt.
"She was a quite high-class member of Wellington society but what threw the authorities was her cross-dressing," said Davidson.
"By 1915/16 toleration of difference was beginning to harden. Because she was of questionable nationality - people weren't sure if she was German or Danish - someone tipped off the authorities that she could be a spy.
"The police raided her home and confiscated her letters, which turned out to be love letters to women."
"You have someone who's confronting gender norms and sexuality during the First World War but there's also that question of her heritage and citizenship and is she a spy."
The police had her examined by a doctor to determine her sex - "so quite an invasion of privacy. That's the kind of information that the Secret Registry contains".
"Because of the state's surveillance of these extraordinary people we have snippets into lives that we may have never been able to look into if the file or the letter was not detained."