On Wednesday, two military cargo planes carrying 55 aluminum coffin-shaped cases landed at Hickam Air Force Base in Oahu, Hawaii. Inside are presumed to be the remains of American service members who died in North Korea between 1950 and 1953 during the Korean War. The remains were turned over to United States officials Friday by the North Korean government — the first such handover since joint recovery efforts between the two countries came to a halt in 2005.

[The 55 cases delivered on Wednesday are likely to contain a jumble of bones and few reliable clues to their identity.]

With the boxes now on American soil, it falls on the Defense Department to begin the difficult task of putting names to those skeletal remains, which could take months, if not years. Leading this effort is a specialized unit out of Hawaii called the Defense P.O.W./M.I.A. Accounting Agency, or D.P.A.A., which was established in 2015 after the Joint P.O.W./M.I.A. Accounting Command and the Defense Prisoner of War/Missing Personnel Office were merged. D.P.A.A. is responsible for locating and identifying the bodies of the tens of thousands of American military personnel who died as prisoners of war or who were considered “missing in action” from World War II to the present.

[Get a weekly roundup of Times’ coverage of war delivered to your inbox. Sign up here.]

The Times Magazine spoke with Dr. Paul Emanovsky, a forensic anthropologist for D.P.A.A. who has been identifying missing American military personnel since 2002, to understand what the agency’s work encompasses and what steps it takes to make an identification.