This article discusses suicide and may be distressing.
John Beckenridge sent a raft of "concerning and aggressive" messages to his "closest friend" leading up to his disappearance, even hinting at leaving on a Russian submarine.
"I thought he was going to do something irrational, hurt somebody maybe," the friend told the court.
Swedish-born helicopter pilot Beckenridge broke a court order by collecting his 11-year-old stepson Mike Zhao-Beckenridge from his Invercargill school on 13 March, 2015.
A week later, Beckenridge's 4WD Volkswagen Touareg went off the cliff near Curio Bay, in Southland. But when police recovered the vehicle there were no signs of any bodies and the two have been missing since.
However, Mike's mother Fiona Lu is convinced her son is alive and that her former partner, Beckenridge, staged the pair's death after she moved Mike from Beckenridge's Queenstown home to Invercargill with her new partner, Peter Russell.
Now, Coroner Marcus Elliot is looking into the case at the Christchurch District Court to consider whether it is likely the pair are dead.
On Thursday evening, the court heard from Beckenridge's closest friend who shared a "strong bond" and a great deal of trust with the missing man.
The friend said he noticed Beckenridge's mental state deteriorating after Mike was placed into his mother's care.
"John was quite upset, I could feel it when I was talking to him. He was sort of depressed and didn't know what he was going to do," the man said.
In a letter, Beckenridge said: "Just trying to survive the holocaust ... life is not funny and certainly no good anymore!"
The man said while Beckenridge could be stubborn, he "had a heart of gold" so it was out of character when he became "hateful and aggressive" toward Lu in the messages he sent.
Lisa Preston KC, assisting the coroner, questioned a sentence in the letter Beckenridge had written to his friend about him and Mike getting on a Russian submarine
However, his friend brushed this off as a joke Beckenridge would make when he wanted to get away from people. He said Beckenridge never spoke to him about a potential escape.
As days went on the friend became more concerned for Beckenridge, and worried he "might do something stupid" as his frustration towards the legal system escalated.
"I thought he was going to do something irrational, hurt somebody maybe."
Beckenridge was saying that there was no more "Johnny be good", and that a different side to him would come out, his friend told the court.
The friend had a phone conversation with Beckenridge and told him not to do anything drastic or something he might regret. Beckenridge agreed, he said.
A few days later the man received a call from the police, informing him about his friend's disappearance, which came as "a shock", the court heard.
No 'goodbye' text
The man said he was left wondering why most of Beckenridge's friends received a "goodbye" text, but he didn't.
"He might have already started something that he didn't want to let me in on so I could stop him," he told the coroner.
The last message the friend ever received from Beckenridge was on the morning he disappeared, saying he would call him later in the day.
"Okay, give me a call when you are home," his friend replied.
The man said he never thought Beckenridge could hurt Mike, but he is convinced the pair are dead.
"To me, there is no doubt he committed suicide."
Last week, at the outset of the inquest, Lisa Preston KC outlined the case. She said Beckenridge met Mike's mother, who is from China, in 2006. Lu's parents were raising Mike at the time.
The pair later moved with Mike to Queenstown. Their relationship broke down in 2014. Shortly after that, Lu moved to Invercargill.
In February 2015, the Queenstown Family Court made an order that Lu should have care of Mike.
Mike was unhappy to be taken away from his stepfather and was secretly communicating with him by email, pleading for Beckenridge to come and take him away from his mother and her partner.
On 20 March, a week after the pair disappeared, Beckenridge's friends began receiving "concerning" texts from him, stating the "Gestapo" was after him and Mike, and they would soon get on the "Midnight Express" for departure.
On 22 March, items belonging to the Beckenridges such as clothes and car parts washed ashore in the Curio Bay area. Soon after, Beckenridge's vehicle was found at the bottom of the cliff.
The police national dive squad was able to investigate the wreckage on 29 March but it wasn't until 6 May that the vehicle could be recovered. No bodies were found.
To date, police have had 60 suspected sightings of the Beckenridges or their vehicle, some of which have been deemed unlikely or they have been eliminated.
Information about possible sightings continues to be reported from within New Zealand and from Kiwis overseas.
The hearing continues.
This story was first published by the New Zealand Herald.
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