The remains had been interred in a group burial service with horse-drawn caissons and a white-gloved honor guard, while their families looked on, clinging together like survivors from a storm. One of the daughters had written Finn a note of gratitude, telling him that despite the revived grief, there was also a sense of relief that she was finally able to lay her father to rest.

More than a thousand veterans still remained unaccounted for, and his father, Richard Arthur Finnemore, was one of them. For years, Finn had searched for his father’s likeness in the faces of panhandlers outside veterans’ halls, wondering if torture had left him impaired and unable to make his way back to his family.

Finn picked up a small scrap of paper from a marker in Section 60, where the recently fallen were laid to rest. The handwritten note said, I have to leave you here. You should be home playing with our kids and laughing with us. But this is where you’ll stay. Forever. I guess in that sense, I’ll never lose you. Despite the summer heat, Finn felt a chill as he dutifully photographed the marker and added the note to his collection.

Finally, he consulted an app on his phone and located the new marker of a very old casualty—army air forces first lieutenant Robert McClintock. Finn had scoured the countryside around Aix-en-Provence, where he was living and teaching. His research had led him to the crash site of a single-seat P-38 aircraft, piloted by McClintock on a strafing mission against an enemy airfield in 1944. Combing through archives, Finn had discovered that on the day in question, poor weather conditions had impaired visibility. A scrap of news on a microfiche had reported that McClintock’s aircraft had dived through the clouds and seemingly disappeared.

With a group of private citizens, Finn had worked with a recovery team, finding teeth and bone fragments, all that was left of the twenty-one-year-old airman. The Armed Forces DNA Identification Laboratory matched three sisters from Bethesda, and last year, Lieutenant McClintock had been repatriated here at Arlington. Finn had not attended the burial, but now he stood looking at the freshly etched marker. Again, there had been letters of gratitude from the family.

He appreciated the kind words, but that wasn’t the reason he did what he did. He let people think he was looking for accolades and recognition in his academic work, because it was easier to explain than admitting that he was really looking for his father.

Standing amid the sea of alabaster headstones, Finn felt a breeze on his neck, redolent of fresh-cut grass and newly turned earth. Where’d you go, Dad? he wondered. We’d all love to know.

The roll of film his sister had found, with his father’s initials on the small yellow can, was the best hope of finding out. The film expert, Camille Adams, was finally going to reveal his father’s last images, taken somewhere in Cambodia decades before.

The thought made him lengthen his strides as he headed for his rental car. Maybe the courier charged with picking up the processed film would be back already. Finn got in and grabbed his mobile phone from the console. It indicated multiple voice mails from the courier company. As he tapped the phone to play the messages, Finn thought, Please, Camille Adams. Don’t let me down.