They themselves didn’t smell much better. They were filthy from wearing the same clothes and sleeping on the rock and dirt floor. Their hair was hopelessly matted. Kevin’s face was covered with a two-day stubble. They were all weak from lack of exercise and food although each had eaten some of what was brought to them.

Around ten o’clock that morning, there’d been a sense that something abnormal was happening. The animals had become agitated. Some had rushed out only to return moments later, making loud cries. Early on, bonobo number one had gone out but had yet to return. That in itself was abnormal.

“Wait a second,” Kevin said suddenly. He put up his hands to keep the women from making any noise. He strained to hear by turning his head slowly from side to side.

“What is it?” Melanie asked urgently.

“I thought I heard a voice,” Kevin said.

“A human voice?” Candace questioned.

Kevin nodded.

“Wait, I just heard it!” Melanie said with excitement.

“I did, too,” Candace said. “I’m sure it was a human voice. It sounded like someone yelling ‘okay.’ ”

“Arthur heard it, too,” Kevin said. They’d named the bonobo who most often stood guard at the lip of the small cave Arthur for no particular reason other than to have a way to refer to him. Over the long hours, they’d had what could have been called a dialogue. They’d even been able to guess at some of the meanings of the bonobo words and gestures.

The ones they were the most sure of included “arak,” which meant “away” especially when accompanied by the spreading of fingers and a sweeping arm motion, the same gesture Candace had seen in the operating room. There was also “hana” for “quiet” and “zit” for “go.” They were very sure of “food” and “water,” which were “bumi” and “carak” respectively. A word they weren’t too sure of was “sta” accompanied by holding up one’s hands with palms out. They thought it might be the pronoun “you.”

Arthur stood up and loudly vocalized to the few bonobos remaining in the cave. They listened and then immediately disappeared out the front.

The next thing Kevin and the others heard were several reports from a rifle: not an ordinary gun but rather an air gun. A few minutes later, two figures in animal-center coveralls appeared silhouetted against the hazy, late-afternoon sky at the cave’s entrance. One was carrying a gun, the other a strong, battery-powered lamp.

“Help!” Melanie shouted. She averted her eyes from the strong beam of light but waved her hands frantically lest the men not see her.

There was a loud thump that echoed around the inside of the cave. Simultaneously, Arthur let out a whimper. With a confused expression on his flat face he looked down at a red-tailed dart that protruded from his chest. His hand came up to grasp it, but before he could, he began to wobble. As if in slow motion, he sagged to the floor and rolled over onto his side.