As she waved goodbye to her husband at the Phoenix airport on that hot, dry Sunday morning of May 30, 1982, little did Ruth Schrock realize that this would be the last time she would see him alive.

After spending five months teaching in Japan, Professor Nicholas Wickham Schrock had reunited with his wife for a short visit in Arizona. She was now returning to their home in Boulder, Colorado. He was taking a different path, crossing the U.S.-Mexican border at Nogales in his pickup truck and heading for a summer teaching program in Guadalajara.

He never arrived.