On September 25, 1997, the Mossad attempted to assassinate Khaled Mashal, then the Head of the Political Bureau of Hamas, in Jordan. The attempt failed, and let's just say, this is an operation the Mossad and Israel would like to forget.
Khaled Mashal was, well he still is, a Hamas leader and a great enemy of Israel. He is responsible for the deaths of many Israelis over the years. In 1997, one of the most horrific suicide attacks Israel has ever experienced took place in Jerusalem. Two suicide bombers exploded in the middle of the Mahane Yehuda Shuk in Jerusalem, killing sixteen Israelis and injuring hundreds more. The decision was made - the Hamas leadership had to get hit. After some deliberation, the target was set - Khaled Mashal.
After the Peace Agreement with Jordan was signed, Rabin prohibited the Mossad from operating in Jordan. As a result, all of the intelligence had to be gathered and arranged from scratch, as Mashal was located in Aman. Prime Minister Netanyahu wanted the assassination to be as secret and quiet as possible, so the plan was that two Mossad agents would walk behind Mashal on the street, and as one of them would open a shaken soda can, the other would spray Mashal with a lethal spray.
The agents arrived in Aman under fake Canadian identities on September 25th. The agents were informed that the target was arriving, and this is where everything went horribly wrong. The agents weren't aware that Mashal's kids were in the back of his car, and as they approached him from behind, Mashal's daughter opened the car door, as he turned towards her, the soda can didn't open and the other agent sprayed Mashal mistakingly on his ear.
Mashal ran to his car and the agents began fleeing in the getaway car. A Hamas member that was in the area by chance, noticed the commotion and began pursuing them. After several hundred meters they exited the car and got into a struggle with him. After a big commotion began at the spot, both Mossad agents were taken away by the Jordanian police.
After the Canadian Consulate arrived at the police station, they verified the two weren't real Canadians, resulting in the head of the Mossad, Dani Yatom, quickly fly over to King Hussein and explain everything to him. After King Hussein told Yatom that if Khaled Mashal was to die from the poison, he would have to sentence both the agents to death, a Mossad agent that carried the antidote gave it to the Jordanians and Mashal's life was saved.
The whole story was really quite a mess, Khaled Mashal survived the assassination attempt, and continued on with his deadly acts against Israel. The Israeli-Jordanian and Israeli-Canadian diplomatic ties suffered a huge blow, and Israel had to release 70 Palestinian prisoners, plus Sheikh Ahmad Yassin, one of Israel's top wanted terrorists, in order to free the two Mossad agents in Jordan.
Israel, and specifically the Mossad, has executed many historic and successful operations over the years, some of them aren't even known to the public yet, and some have been turned into internationally acclaimed movies. Unfortunately, this is just one of the less successful stories that we would just like to forget.