When Johnny Isakson stepped off his plane after his 16-hour flight to Benin a few days ago, he was greeted with news that augured a good stay in that tiny west African country.

An official on the tarmac immediately informed the U.S. senator that the five suspects he was interested in had finally been separated. No longer were they in the same work camp, where they could keep their stories straight. They were now scattered across the landscape in five separate prisons.

“So I knew we were making progress,” Isakson said Friday back in his Atlanta office.

Five years ago this month, a 24-year-old Peace Corps volunteer from Cumming was murdered as she slept in the Benin village of Badjoude, where she had been posted as a teacher since 2007. Kate Puzey’s throat had been slit hours after she had reported a local, male Peace Corps staffer for molesting village girls.

The man’s brother, it turns out, worked in the Peace Corps’ in-country headquarters, where Puzey had directed her confidential message.

At the family’s behest and with their help, Isakson has spent the past several years urging the Benin government not to allow the homicide prosecution to fall through the cracks. In 2010, after an investigating judge said there was not enough evidence to move the case forward, Isakson flew to Benin to make a personal appeal to that country’s president, Thomas Yayi Boni.

The case was not dropped. In fact, a special agent from the FBI’s office in Lagos, Nigeria, was brought in to help. But after a lurch forward, the process had again stalled.

And so Isakson went back to Benin this month. But this time the senator was met there by Kate Puzey’s surviving family — brother David and mother Lois. Kate’s father, Harry Puzey, died in 2012 after a long bout with cancer.

“We were kind of at this wall. Nobody would talk, nobody would cooperate,” Isakson said. “So we got the FBI cold case squad to make recommendations to the Benin government.” One recommendation was the use of a polygraph. The machines had never been used in Benin.

“Our FBI trained Benin officials in the use of polygraph,” Isakson said. Enough information was gleaned to crack a few stories — and prompt the sequestration of the suspects.

The diplomatic purpose of the senator’s mission was to thank the French-speaking president of Benin for permitting U.S. law enforcement to assist in the case.

Isakson and the Puzeys had a two-hour session with Yayi. They were also introduced to a new and aggressive investigating judge — who immediately spent an additional several hours deposing the Puzeys, mother and son.

Justice is still no sure thing, but it seems to have inched closer.

“It was great. (The judge) took my notes and asked his own questions. He’s very intent. He’s a new one on the job. But I could tell he was very sincere that he wanted to bring this case to trial,” Lois Puzey said. “The president and the Cabinet — it’s a matter of shame for them, and they want it closed. The problem is at the village level, where they’re afraid to talk.”

Lois Puzey was on her cellphone. She’s in the middle of closing up the family’s home off Ga. 400 and relocating to something smaller in Florida.

She only got back Monday. The Peace Corps mother and son stayed on in Benin after Isakson left to make the bittersweet journey to Badjoude, a two-day trip.

A thousand or so villagers, many wearing Kate Puzey T-shirts, greeted the two Puzeys for a daylong ceremony. The local school and library now bear Kate Puzey’s name. A Mass was celebrated and a medal struck in her honor.

“I cried about it at the end, but I could still see why Kate loved Africa so much, and how she could think that she was sitting in her world,” Lois Puzey said. “I really got it, even though to us the price was too precious.”

On Wednesday, Isakson took to the Senate floor to mark the fifth anniversary of Kate Puzey’s death. “I don’t know what the ultimate result will be, and I want justice to be done, I want the right person to be persecuted and prosecuted and the right person to pay the price, but I want closure to come for this family,” he said.

Two hours before the senator gave that speech, I was in the truck on the way to downtown Atlanta. My cellphone rang. It was my own Peace Corps daughter calling from her shack in Paraguay.

She was slightly shaken. One of her group had died the night before — a quiet, 27-year-old fellow from Kentucky. His was the second death of a Peace Corps volunteer in March. In neither instance is foul play suspected.

Nonetheless, the fatalities were an unwelcome reminder. The Peace Corps is an arm of what is termed “soft” U.S. diplomacy. By definition, its volunteers do not stand, arms akimbo, in harm’s way. But at the edges of the world, harm often casts itself where it will.

Emily’s hitch will be over around Christmas. We will be happy that she did it, and happier still that it’s done.