It had taken the Hermann’s more than two years to convince the Israeli’s to believe their story, so when Aharoni arrived in Argentina it was no surprise that he discovered Eichmann’s residence deserted. Eichmann had moved just days before. Had the window of opportunity gone?

Fortunately, after weeks of investigating, Aharoni was able to track down one of Eichmann’s sons who still worked in the area. After tailing him back to his new home on Garibaldi Street, in San Fernando, Buenos Aires, Aharoni was able to set eyes on Eichmann for the first time. Using a camera hidden in a briefcase he snapped black and white photographs of the balding 54-year-old.

Although Mossad had a wartime photograph of Eichmann from the early 1940s, they had no real idea what he looked like in 1960. Aharoni soon returned to Tel Aviv and Israeli identification experts went to work on the photos he had captured. Although not 100% sure, the experts concluded that the man in the photographs was most likely Eichmann. It was enough to convince Harel.

Since Argentina had a history of declining extradition requests for Nazi war criminals, the decision was made to capture Eichmann covertly and bring him back to Israel for trial. David Ben-Gurion, Israel’s Prime Minister at the time, approved the order and greenlit the operation.

Mossad was still in its infancy as an intelligence service so this operation was by no means an easy feat. They put their best men on the job, including Harel himself who flew out to Buenos Aires to oversee the capture. The eight-man task force arrived in Argentina in April 1960, led by Mossad operative Rafi Eitan.

After carefully watching Eichmann for a number of days they began to learn his routine. The plan was to snatch him as he walked home from work, keep him at a designated safe house before flying him back to Israel. In those days flights didn’t happen all that often and so the team would have to hold Eichmann at the safe house for a number of days. They then planned to board him onto an El Al aircraft in Buenos Aires. The aircraft would be there after bringing Israeli delegates over for the 150th-anniversary celebrations of Argentina’s independence from Spain.