LYON, France—In China, she enjoyed the privileges that flowed from being married to a senior member of the Chinese Communist Party’s (CCP) elite. Her husband was a top police official in the security apparatus that keeps the CCP in power, so trusted that the regime sent him to France to take up a prestigious role at Interpol. But Meng Hongwei, the former Interpol president, has now vanished into the CCP’s sprawling penal system, purged in a stunning fall from grace. And his wife is alone with their twin boys in France, a political refugee under round-the-clock French police protection following what she suspects was an attempt by Chinese agents to kidnap and deliver them to an uncertain fate. From being an insider, Grace Meng has become an outsider looking in—and says she is horrified by what she sees. So much so that she is now shedding her anonymity, potentially putting …