MURDERED: Malvina Krutz

In the summer of 2015, Mary Yoder, a healthy 60-year-old chiropractor, went to work as usual. Later that day, she began feeling sick. Within two days, she was dead. At first, her sudden decline seemed like a medical mystery. But investigators soon uncovered evidence of poisoning, launching a murder investigation that divided her family and the community.

In 1981, a Harvard graduate student vanished after stepping out of Logan Airport the night after Thanksgiving. As investigators searched for answers, they focused on a suspect connected to another murder – a woman who was killed just two years earlier. He was convicted in one case and widely believed responsible for the other. But after reviewing thousands of pages of records, we found gaps that raise difficult questions: Was the wrong man blamed? And is the real killer still out there?