Driving south on the autobahn in the spring of 1978, a large transporter on the opposite carriageway trundled into my view.

On its trailer were several agricultural machines and stamped in large letters on their sides was the name “MENGELE”.

The merchandise was being delivered from a factory in Gunzburg, Bavaria, founded a century earlier by Karl Mengele, whose son Josef was then one of the world’s most notorious Second World War fugitives.

Josef Mengele had served as an SS doctor at the Auschwitz extermination camp from May 1943 to January 1945.

His family home in Gunzburg was also where I was heading on what in hindsight was probably the most preposterously ambitious venture of my journalistic career: to succeed where both the West German and Israeli authorities had failed — finding Mengele, reported to be hiding in Paraguay under the protection of its President, Alfredo Stroessner, who ran one of South America’s most oppressive dictatorships.

I’d just joined the ITV investigative documentary programme World In Action. In those days, TV budgets were many times bigger than today, so ambition was as high as the sky. We hired a team which included an attractive, blond, blue-eyed German doctor whose task was to use her feminine charms to penetrate the German settler community in Paraguay which is where Mengele was rumoured to be hiding.

Needless to say, we failed to find Dr Mengele. After six weeks of stakeouts and dead ends, we were rumbled. My colleague was arrested, thrown into a cell in the capital Asuncion and deported, whilst I managed to escape across the Paraguayan border into Brazil with some of our film and documents.

But although we never set eyes on Mengele (who, we later learned, had moved to Brazil), our resourceful German doctor did penetrate the circle in which he had moved in recent years, allowing us to covertly record several Nazi sympathisers who had helped him, including one man who admitted to still being in touch with Mengele. When the doctor asked him if he knew where Mengele was getting money from, he replied menacingly: “Do you have to ask such stupid questions? Leave Mengele alone. Now you’re beginning to sound dangerous to me. Now we’ll have to find out what you’re really up to.”

The programme, called The Hunt for Dr Mengele, was also broadcast on the American TV network CBS to 20 million viewers and spurred a congressional campaign to establish a special Nazi-hunting unit within the US Justice Department unit called the Office of Special Investigations (OSI).

The OSI targeted mainly Nazi war criminals who had sought refuge in America, amongst them the Sobibor (and probably Treblinka) concentration camp guard, John Demjanjuk, so savagely violent he was known as “Ivan The Terrible”; the OSI also kicked out a fascist Romanian cleric, Archbishop Valerian Trifa, who in 1941 incited a pogrom against Jews in Bucharest in which over 100 died.

I confronted — and filmed — both Demjanjuk and Trifa in the US. I also spent several weeks in Santiago, Chile, looking for Walter Rauff, the SS colonel who pioneered the use of mobile gas vans whose engine exhaust was diverted into an hermetically sealed rear compartment killing between 100-200,000 Jews. I eventually found Rauff walking his dog. “You’re a lucky man to still be enjoying your freedom,” I said to him, sticking a camera in his face. “Ja” he replied, smiling, totally unphased by the ambush. Six months later he was dead.

Now, en route to Gunzburg, I was hoping that someone in the wider Mengele family might talk to me about their fugitive relative.

To the world, Mengele had become the surviving symbol of Hitler’s “Final Solution” and the incarnation of its monstrosity. To his family he’d been misunderstood. I wanted to ask them why they thought this.

My drive to Gunzburg ended in tears — quite literally. Answering the door of the Mengele family home was a middle-aged woman who began to sob right there on the doorstep when I gently asked her if she might sit down with me.

It was hopeless, of course, and as I left, I noticed a man leaning on the adjoining fence, staring at me hard. I recognised him as the man who’d been identified in the press as the suspected go-between for the Mengele family and Josef some 6,000 miles away.

His name was Hans Sedlmeier, a childhood friend of Josef and now a Mengele company executive.
What I didn’t know then but learned in 1985, when researching a biography of Mengele, was that in October 1977, Sedlmeier had arranged for Mengele’s only son Rolf to secretly visit his father in his Brazilian bolthole. The correspondence between Mengele, his son and Sedlmeier in planning the trip — and its outcome — was disclosed by Rolf to me and my co-author, Gerald Posner.

Rolf was then a 33-year-old solicitor who’d become the black sheep of the formidable Mengele dynasty.  A product of 1960s anti-establishment attitudes, the wealth and power of his cousins, aunts and uncles, whose engineering factory was Gunzburg’s largest employer, never much appealed to Rolf. In fact, he regarded them as bourgeoise and rather petty; he thought they enjoyed local patronage yet took their power for granted.

Weary of trying to resolve the conflict between the horrific allegations against his own flesh and blood and his family’s doubts about the truth of them, Rolf decided to settle the matter for himself by travelling to Brazil to confront his father in person.

Rolf had met his father only once previously, when he was 12, on a fleeting visit from South America to the Swiss Alps. He was introduced to him not as his father but as his long-lost uncle “Uncle Fritz” and only learned of “Uncle Fritz’s” real identity when he was 16.

The questions soon followed and grew only louder in his head with every story published about his father. By the 1970s, the West German Prosecutor had gathered witness statements culminating in 78 separate indictments against Josef Mengele.

One can only wonder at the anguish this must have caused Rolf because the sheer volume of this official testimony extended well beyond the crime with which Mengele is typically associated: his infamous “selektions” at the Auschwitz railhead where trains carrying thousands of Jews crammed into cattle trucks arrived up to five times a day, including at night.

Of all Auschwitz’s cadre of SS doctors, the one most often witnessed as waiting at the railhead was Hauptsturmführer Mengele where, with the wave of his hand or the flick of his polished baton clasped in a white gloved hand, he would decide who would live and who would die.

The vast majority Mengele waved to the left, which meant being led to disrobing huts where they were ordered to strip naked and undergo disinfection in what looked like a vast communal shower room. The doors were then locked, Zyklon B pellets were dropped through the roof which, on contact with air, released deadly hydrogen cyanide gas, suffocating the inmates to death.

The more able-bodied arrivals were waved to the right to be used as slave labour until they too were selected for the gas chambers because they were deemed no longer to be of any use.

Surviving witnesses told the West German Prosecutor they saw Mengele present at 39 “Selektions”, though the actual number would likely have much higher since most witnesses would not have survived.

Selecting those for life or death was a task that Mengele seemed to relish. Not for him the alcohol that even some SS doctors required to deaden their senses when they performed “Selektions”. As a committed Nazi, Mengele took to his task with a detached, haughty air, surveying his prey with a cold, gimlet eye, sometimes smiling or whistling an operatic tune, his chilling demeanour earning him the nickname “The Angel of Death”.
For Mengele, these “Selektions” were about much more than eliminating Europe’s Jews. He’d been dispatched to Auschwitz from the Russian front (where he’d earned an Iron Cross) because, as an extermination camp, Auschwitz provided a laboratory of unlimited raw material in which to pursue his research into perfecting the superiority of the master race.

Here the ambitious, workaholic Mengele could indulge his obsession with devising the most efficient mass sterilization procedures for souls deemed to be racially unhygienic, while breeding ever greater numbers of racially hygienic souls.

Hence Mengele’s obsessive cry at the railhead for “Zwillinge, Zwillinge, Zwillinge” — twins, twins, twins — on whom he would conduct barbaric in vivo experiments before killing them, and then perform comparative autopsies to see if imperfections in the organs of one twin were replicated in the other.

The West German indictment referred to Mengele’s purpose as “the medically manipulated increase in the number of births of twins”. In other words, how the fatherland might fast-breed a perfected master race — research which he hoped would be rewarded with a professorship.

The data from Mengele’s monstrous work and his specimens were dispatched as “War Materials — Urgent” to his mentor at Berlin’s Kaiser Wilhelm Institute for Anthropology, Human Heredity Teaching and Genetics, the geneticist Dr Otmar Frieherr von Verscher. According to the Holocaust scholar Professor Michael Berenbaum, as an outspoken admirer of Hitler, von Verscher regarded him as the “first statesman to recognise the true importance of hereditary biological and race hygiene."

Whilst both gypsies and Jewish twins were Mengele’s raw material, he regarded gypsies as a much lower species than Jews, confiding to a fellow Auschwitz doctor: “There are only two gifted people in the world: Germans and Jews, and it’s a question of who will be superior.” That, wrote the doctor, was Mengele’s own rationale for deciding that Jews had to be destroyed.

As for gypsies, ironically, on account of Mengele’s own distinctly un-Aryan looks (tawny skin, brown-green eyes and dark brown hair) the SS categorised him as “Dynarisch-Ostisch”, meaning his dominant features were of “eastern” origin.

Witness testimony to the West German Prosecutor from both surviving inmates and some doctors and nurses portray a physician of indescribable cruelty as he engaged in a bizarre array of experiments: stitching together the hands and bodies of twins; injecting eyes with dye to see if their pigmentation could be changed (one witness described seeing a wall in Mengele’s laboratory covered with eyes “pinned up like butterflies”); different blood types transfused into bodies of twins; wounds deliberately infected to compare how each twin reacted, even to point of developing gangrene.

When Mengele’s raw, living, human material served no more useful propose, he often had them killed, sometimes with a shot in the back of the head, or by injecting them with phenol, petrol, chloroform, or just with air into the blood circulation, or directly into a heart chamber.

Then there were Mengele’s endurance tests. The West German indictment refers to young girls being strapped to a table and electrocuted because he wanted to see how much electric shock a body could take. A mother’s breasts were taped up to find out how long her new-born baby could survive without milk. Though Mengele profaned the word “science”, right to the end he thought of himself as a scientist.

The Red Army put an end to his career. By Christmas 1944, Mengele realised the game was up as Soviet troops continued their westwards advance across Poland. On 17 January 1945, ten days before the liberation of Auschwitz, he said goodbye to his staff, and took his pseudo-scientific data with him, marking the start of 34 years on the run.

Thirty-three of those years would pass before his son Rolf — for so long, torn by questions about his father’s past — felt he could postpone the confrontation no longer.  “I was fed up with the written arguments” he explained. “I wanted to talk to my father personally.”

In the second part of our series next week, John Ware recounts how Mengele was confronted by his lawyer son Rolf at his Brazilian hideout in 1977. This account is based on letters between father and son and interviews with Rolf