All of the men had known about the Waorani for years as a remote people with no contact with the rest of the world who had a reputation for killing any outsider on their territory. Elliot, McCully, and Fleming were strongly motivated by their faith to reach people who had never heard the Gospel, as was Saint. The Waorani, therefore, were of special interest to them.

Contact became possible in September 1955, when Saint and McCully spotted a Waorani clearing from the air. The men called this cluster of homes “Terminal City.” A few years earlier, Saint, an aviator with Mission Aviation Fellowship, had developed an innovative means for talking with people on the ground without landing. It involved lowering a phone in a bucket from a small plane to the ground, while the pilot flew in a careful circular pattern that made it possible for someone on the ground to grab and speak into the phone. Saint refined the method to become what he called “the bucket drop,” whereby physical objects were transferred between air and ground.

In October and November, Saint—sometimes accompanied by McCully or Elliot—began to make contact with the Waorani from the air via the bucket drop with small gifts. The Waorani began to send up some gifts in return, including a parrot. These gifts encouraged the men to believe that friendly contact was possible. They also began using a loudspeaker to broadcast brief messages in what they thought was the Wao language, proclaiming their friendliness. In all, Saint, McCully and Fleming made 12 flights over the Waorani clearing.

The men had picked up some Wao phrases from Dayuma, a Waorani who had fled her village in fear of her life some 11 years earlier. She was working as little better than a slave on the hacienda of a local landowner, when Elliot and Fleming made contact with her. They picked up a few words and phrases from her, which they hoped would be useful.

However, complications led to the tragic consequences. The five were keeping the project secret from everyone except their wives and some MAF personnel. Dayuma wasn't told about the project, and neither was her friend Rachel Saint, Nate’s sister. And none of the missionaries knew that Dayuma had forgotten or repressed much of her knowledge of the Wao language after not speaking it for more than a decade. The phrases they used, therefore, were in a broken form of the language and could not be understood by the Waorani they sought to contact.

Fleming was conflicted about whether God was calling him to participate. He was concerned about risking the lives of all three missionaries crucial to the Quichua work, and he and his new wife had only recently arrived at their jungle mission station. In light of Fleming’s uncertainty, Elliot and McCully looked for a possible third man. At Nate Saint’s recommendation they invited Roger Youderian to join them, because of his experience as a pioneer missionary among the Jivaroan peoples. (Unknown to Saint, Elliot and McCully, Youderian was deeply discouraged over the lack of apparent success among the Jivaros and was thinking of leaving the mission field.) In the end, Fleming resolved his doubts and Youderian broke through his discouragement. Both chose to participate.

On January 2, all five men gathered at Arajuno, the McCully’s mission station, and the next day Saint flew Elliot, McCully and Youderian and the supplies to a sandbar on the Curaray River, a few miles from Terminal City. The next day, he brought Fleming as well. They called their camp "Palm Beach," set up a prefabricated tree house, and prepared a landing strip for the plane.

The following is the reconstruction of the Waorani’s view of the event, based on accounts from several participants given over several years, accounts that sometimes contradict each other in details.

On January 6, the camp was visited by three Waorani – a man the missionaries nicknamed George (real name Naenkiwi), a young woman they nicknamed Delilah (real name Gimari), and an older woman named Mintaka. Gimari, sister of Dayuma, wanted to know if these strangers knew anything about her sibling. Naenkiwi wanted Gimari for his wife and had followed her. Mintaka, Gimari’s aunt, came as a chaperone.

There followed a long, friendly visit that lasted from about 11:00 a.m. until late afternoon, when Naenkiwi and Gimari left. Gimari tried to ask about Dayuma, but the missionaries did not understand what she said. During the afternoon, Saint took Naenkiwi for a plane ride over Terminal City. The Waorani man was delighted. The people below recognized him, and some resolved to visit the strangers the next day. After “George” and “Delilah” left, Mintaka stayed much longer, talking with the missionaries all night.

On January 7, Naenkiwi and Gimade, on their way back to their village, came across another, larger party of Waorani, which included Gimari’s brother, Nampa. They were also going out to visit Palm Beach.

Nampa was furious to see his unmarried sister with a man who wasn't an appropriate potential marriage partner. Naenkiwi, to deflect his anger, said that they visited the five strangers and were attacked. The two of them fled and were separated from Mintaka, their chaperone. The Waoranis' anger over the “attack” and suspicion of strangers laid the groundwork for a real attack on the men at Palm Beach. On the way back to their houses, they resolved to attack the strangers the next day, and were not dissuaded, even when Mintaka joined the group and said the missionaries were friendly and there had been no attack.

At about 3 p.m.in the afternoon on January 8, a party of six men (Gikita, Nampa, Nimonka, Kemo, Yowe, Minkaye) and four woman (Akawo, Mintaka, Dawa, Meñemo, although some accounts say there were only three women) approached Palm Beach. Some of the women appeared on the opposite side of the river from the missionaries’ camp. Elliot and Fleming started to wade across the river to greet them.

Elliot was speared in the river, Fleming when he reached the other shore. Saint, McCully, and Youderian were killed around their campsite, as Youderian was probably trying to reach the radio. Saint’s watch was found, stopped at 3:12 p.m. The men had rifles and at least one revolver with them at their campsite. Although they did not use the rifles to defend themselves, the revolver was fired—it’s not clear by whom—in the midst of a struggle.  The bullet hit or grazed Nampa, causing a wound that eventually led to his death.

The Waorani then attacked the plane, tearing off the canvas on the wings and otherwise destroying the camp.  They then went back to their houses, burned them down as was customary, and fled into the jungle. According to reports beginning in the late 1980s, Dawa, Kemo, and Yowe (Dyuwi) all said after the killings they heard singing and saw lights over the tops of the trees.

Nate Saint told his wife Marj that he would be calling in on the radio at 4:30 a.m. Anxiety began to mount when no call came in. On the morning of January 9, Johnny Keenan, an MAF pilot who worked with Saint and the others on the project, flew over the site and saw the destroyed plane—but no sign of the men. A search party was organized from missionaries, Quichuas, and U.S. and Ecuadorian military. Between January 11 and January 13, they sighted all the bodies, although McCully’s body—identified by an advance party of Quichuas, who recovered his watch and shoe later—had disappeared down river. Amid a serious storm, the other four men were buried on January 14 and the search party returned home.