The wife of sacked Communist Party official Bo Xilai made quite an impression when she showed up in Mobile, Ala., 15 years ago with her young son in tow. Denver lawyer Ed Byrne, whom she had hired to represent Chinese companies embroiled in a legal mess in U.S. federal court, was struck by her brains, charm and beauty. Gu Kailai, he says, seemed like the "Jackie Kennedy of China."

The business cards she distributed carried the name Horus L. Kai—a name she used in various business...