IT WAS THE SUMMER OF '67—THE season of Sgt. Pepper, flower power and Vietnam War protest. The country was in ferment, and Pfc. Allen Adams had plans. A supply specialist at Fort Myer, in Arlington, Va., he was entranced by the emerging world of computers, as well as less cerebral distractions. In a letter home he told his mother, Betty, that he hoped to drive to Miami on vacation with "two cute civilian girls" from work and maybe—if he could save $500—buy a car of his own. "Will write sooner next time," he promised, but next time never came. One night in July, Allen Adams disappeared.

Days later, Betty Adams and her husband, Darrel, received a letter from the Army reporting that Allen, 20, hadn't returned to duty. By then the Army had classified him AWOL. Yet for 30 years his family refused to accept that verdict and never lost hope they would see him again. "I just kept pretending he would come through the door and surprise us," says Betty, 64. "You never stop looking."

Her vigil finally ended Dec. 18. A bulldozer operator in Washington, demolishing the ruins of a long-abandoned building that had once housed a pool hall, spotted a pair of tattered blue jeans in the rubble and a leg bone protruding from the waistband. From dog tags found in a pocket and, later, DNA testing, police confirmed that the remains were those of Adams—and found themselves investigating a murder three decades old.

The discovery brought little comfort to Betty Adams and her family, who had never believed that Allen, who reenlisted in the Army two years before his disappearance, had deserted. "It is just not a relief to know that your son is dead," says Betty, leafing through old photos of Allen in her Hickory, N.C., home. Now her grief is mingled with frustration. "We tried so hard for so long to get help from the Army and couldn't," Betty says. "One big 'Why?' has just been replaced with another."

Police can offer few answers. So far they have one possible witness—the owner of one of the businesses that operated in the now-demolished building—and a sketchy outline of Adams's movements on that final night. At some point, Adams headed for the Crown Bar and Grill, a popular military hangout located one floor below the Apex Billiard Parlor, where he had often shot pool. There the trail ends. "He probably never left the building," says investigating police officer Lt. James Boteler, who adds, "From what we have been able to determine, he was a fine young man." Concealed on the vacant third floor or in the attic, Adams's body escaped detection.

"I knew something desperate had happened," Betty says. "There was no way he would ever leave and not be in touch." Not only was Allen a diligent correspondent, but he was close to his brother David, then 18, and to his sisters Beverly, 10, and Pamela, 6. "He was always my hero," says Beverly, now 40 and a homemaker in Hickory. "He taught me to play ball—baseball, football, all kinds." Growing up in West Palm Beach, where Darrel, now 69, worked in an aircraft-parts factory, the brothers were inseparable, camping out on a nearby pier or fishing with homemade rods in a boat they had built. An average student, Allen left school at 17 to join the Army, serving a year in Korea after reenlisting in '65.

In June 1967, Darrel drove David and the girls to Washington to visit Allen. (Betty, who managed a small drive-in restaurant, stayed behind.) "For the first time, he seemed to have a real sense of purpose, a real niche in life," recalls David, now 48 and a retired fireman living on a farm in Richland, Ga. Weeks later, Allen was gone.

When the family tried calling the Army, Betty says, the answer was always the same: "We can't tell you anything. Your son is AWOL." For years after his disappearance, law-enforcement agents would stop by the family's home, demanding to know where he was. With no official help, Betty and Darrel searched for their son through the Red Cross, the Salvation Army and missing children's networks. "I was sure that someone, somewhere had seen him," Betty says.

Eventually the family tried not to talk about Allen. "I just couldn't handle it," says Betty, who learned to hide her tears from the children. "It was only on Allen's birthday and Mother's Day that she'd break down," says Beverly, who now has two kids of her own. "Those were the hardest days."

Although Adams was laid to rest in February with full military honors, the investigation of his murder will continue until "we make an arrest," says Lieutenant Boteler. "There is no statute of limitations on murder." Says Darrel Adams: "Until we find out what happened to our son, it will never be over for us."

ANNE-MARIE O'NEILL
GAIL WESCOTT in Hickory and SCOTT BOWLES in Washington

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