As chairman of J. Walter Thompson, the fifth largest advertising agency in the U.S., Joseph O'Donnell was one of Madison Avenue's golden boys. During his ten years at the agency, he had raced ever upward through the ranks. At the start of the year O'Donnell at 44 had defeated several rivals to become the chief at Thompson and the heir apparent to Don Johnston, the 59-year-old chairman of the J.W.T. Group, the holding company (estimated 1986 sales: $650 million) that owns the ad agency. Further triumphs seemed assured.
No more. Just three weeks after his promotion, O'Donnell was suddenly missing from...