Looking at the medical mystery behind the thallium poisoning case of Chinese college student Zhu Ling. In 1994, a bright, young college student in Beijing suddenly fell dangerously ill. As her condition worsened and doctors scrambled for answers, no one could explain what was happening. A blog post from her friends uncovered the truth: she was being poisoned. But the discovery raised more questions than it answered. Who was targeting her, and why? Today, we’re looking at the Thallium Poisoning of Zhu Ling.