Relentless disappointment seems a hazard of the job when you’re one of the world’s few Nazi hunters.
So Dr Efraim Zuroff has come up with a personal reward system to help him cope.
It’s not that tracking down a Nazi is even the hardest bit, or achieving some kind of legal action, although that’s tough.
It’s managing to get anywhere at all before this fast-ageing population of some of the world’s most heinous criminals “croak”, explains Efraim.
“You know how many died on me in mid-investigation?” asks the American, weariness clear in his voice.
“I had to make a scale of achievement, with points, to console myself.
“One point for exposing the person, two for a government investigation, three to have a charge, four is a trial, five is convicted, and six, punished. I’ve only ever had a handful of sixes.”
In fact, of the 3,000 names he has handed to governments over his four-decade hunting career, he’s seen only around 40 result in legal action and not necessarily a trial and sentencing.
But he adds: “Sometimes exposure is the most painful thing to them, if their families find out what they did.
“It’s a race against time. Every day I pray for the good health of Nazis – I’m the only Jew in the world who does that! I feel the pressure so much.”
Now, 75 years after the end of he Second World War, Nazi hunting is the subject of Amazon’s new drama series Hunters, which started last night.
It stars Al Pacino as a vigilante scouring New York in 1977 for Nazis threatening a Fourth Reich in the US.
His team of renegades takes a less painstaking approach to justice than Efraim – assassinating targets in the most gruesome way rather than risking a natural death as they wait for grinding legal wheels to turn.
Clearly, the plot is fantasy and it’s not an approach Efraim advises – but it probably does away with Pacino’s need for a consolation points system...
One inspiration for the series, minus the killings, is the most famous Nazi hunter of all, the late Simon Wiesenthal, a Holocaust survivor who brought around 1,100 Nazis to justice.
They included Adolf Eichmann, architect of the Final Solution and Karl Silberbauer, the Gestapo officer who arrested 14-year-old Dutch diarist Anne Frank and sent her to her death.
Wiesenthal was in a sense Efraim’s predecessor. The human rights organisation he works for, the Los Angeles-based Simon Wiesenthal Center, was named for him.
Born in Buczacz, Galicia – then part of the Austro-Hungarian empire and now Buchach, Ukraine – engineer Wiesenthal experienced an unimaginable 11 concentration camps.
He attempted suicide three times and ultimately spent six nights in a freezing open freight wagon destined for Austria’s Mauthausen camp.
There he was left to die, incapable of hard labour, even by Nazi standards.
When the Americans liberated the camp in May 1945 he was barely alive yet his brain was whirring furiously.
He made a list of Nazi officials and guards and convinced the US officer in charge to let him help the Americans track them down.
Barely more than a walking skeleton, his career as a Nazi hunter had begun before the rest of the world had fully grasped what the Holocaust meant.
By 1947 he was working independently, obsessed with Eichmann, whom he tracked relentlessly.
Wiesenthal claimed to have found Eichmann’s hiding place in Argentina several years before Israeli intelligence captured him in 1960.
The arch-Nazi’s trial the following year was famously televised and brought Wiesenthal fame, fuelling his Nazi-hunting career which he eventually ran from a centre in Vienna.
Despite neo-Nazi death threats he was never deterred. Before he died in 2005 he had received plaudits from around the world, a Nobel Prize nomination and an honorary knighthood.
Israel-based Efraim, 71, met him many times to discuss their joint vocation – although they were a far cry from Pacino’s vengeful gang in Hunters.
He says: “Simon’s work is an inspiration, no question. I’m his successor. I feel that on my shoulders.
“We are carrying on his work in the way he wanted – not to go out and assassinate Nazis but to try and bring these people to justice and turn those trials into history and morality lessons for a world that needs to be reminded.
“He was dead set against revenge and taught me it does not solve the problem. I also learnt perseverance.
“But most important was the obligation we owe to the victims. That came up time and again. It’s a powerful point.”
Efraim’s parents, originally from Lithuania, lost family in the Holocaust and he is named after his great-uncle who died at Nazi hands.
A trained historian, he began work with the Wiesenthal Center as a researcher. When the centre opened in 1977 – the year in which Hunters is set – it wasn’t focussed on Nazi hunting.
However, as it emerged thousands of ex-Nazis were still at large, the US Justice Department approached him to work with them.
That’s where his Nazi hunting began. In 1986 came a “eureka” moment when he realised refugee records in Israel contained the names of many Nazis who had posed as displaced persons.
His knowledge of Nazis meant he had names. All he had to do was cross-check these with Red Cross records to find where they had emigrated to and now lived.
He went back to the Wiesenthal Center with a mission not only to hunt Nazis but also to convince the countries they were hiding in to prosecute.
He says: “I became the chief Nazi hunter and have been ever since. We had to swamp them with suspects so they couldn’t walk away from it.”
In time, laws to allow prosecutions were passed – Efraim sees them as “scalps”.
In the UK that landmark came in 1991, although only one Nazi has since been prosecuted here, despite Efraim giving Britain a list of 17 suspects.
He says: “We knew it was the tip of the iceberg but none were prosecuted. None is still alive as far as I know.”
Some survivors are unwilling to give evidence. But many more are.
The nation most willing to prosecute is Germany, where the trial of ex-SS guard Bruno Dey, 93, is ongoing in Hamburg.
His is accused of being an accessory to the murder of at least 5,230 inmates at Stutthof in Nazi-occupied Poland.
Efraim was involved in finding more than 20 survivors willing to give evidence and is confident the trial will result in a conviction as long as Dey lives. “I’m praying for his good health,” he says.
He dismisses reports this could be the last Nazi trial. “Of course there’s time. The Germans have announced 23 additional investigations,” he says.
He and his team work on tip-offs, offering up to €25,000 for information.
For all his frustrations, there are numerous successful cases.
His personal best, he says, was the trial of Dinko Sakic, a pro-Nazi who ran Jasenovac camp, “the Balkan Auschwitz”, in Croatia in 1944.
He was found guilty in 1998 and sentenced to 20 years. Efraim recalls how his team tracked down the
Croatian and confronted him.
He says: “He wasn’t really hiding. It wasn’t hard to find him but no one had bothered him for more than 50 years.
“It was one of the most amazing interviews because he said he would do it again. Normally a Nazi will say ‘It’s not me’ or ‘It’s me and I didn’t do it.’”
One day in 1944 Sakic began picking inmates at random to be hanged. A Serb said hanging was against his culture so Sakic shot him in the head.
What happened after the verdict 54 years later, Efraim carries around with him always. It’s a prime motivation.
He says: “As the court was clearing, a tall, nicely dressed gentleman stopped me and said ‘I only have one thing to say to you: Hvala vam.’ That’s thank you in Croatian.
“It was the brother of that victim. He had never dreamt they would put his brother’s murderer on trial.”
It’s rare for Efraim to confront a Nazi outside court. The idea he turns up at their doors is not reality, although he admits he has tried it twice as “stunts” to put pressure on governments.
The perpetrators weren’t in.
He tries to keep his work impersonal although admits that’s become harder since a recent trip to mass graves in Lithuania, where his family are from.
He explains: “It’s not a question of anger, you can’t let anger get in the way. It has to be determination, perseverance and the sense you are doing something that’s the right thing.
“These b*****ds are the last people on earth who deserve any sympathy.
“But you have to control your emotions otherwise you won’t be effective.”
To anyone who says it’s a waste of time pursuing elderly men and women, he says the same thing. “You see frail old men and women. But at the peak of their physical powers they were using all their strength to murder people, some older than they are today.”
And he adds: “I have never had a case where there has been an apology.”
Ultimately, he says, he works for the survivors, who generally feel an obligation to give evidence for those who did not survive. He sees a weight lift from them when justice is served.
And he believes justice sends a message for all terrorists today.
“You commit crimes like this, then even decades later someone will hold you accountable,” he says.
At a time of rising Holocaust denial and anti-Semitism, the fight is as much about “changing the narrative”.
Will he ever stop Nazi hunting? He maybe weary, frustrated, exasperated, but in short, no. “You’ll never hear me say I’m stopping because too many bad people would be happy,” he says.