respected cancer doctors, accused of plotting to kill another doctor, who happened to be her lover. Abc's gio benitez on the chemical investigators say has been used before to kill. Reporter: Tonight,... See More
respected cancer doctors, accused of plotting to kill another doctor, who happened to be her lover. Abc's gio benitez on the chemical investigators say has been used before to kill. Reporter: Tonight, one of the nation's top cancer specialists is at the center of a twisted case. Oncologist ana maria gonzalez-angulo accused of poisoning her colleague and lover, dr. George blumenschein. Both worked for m.D. Anderson cancer center. And cancer patients travel from across the country just to see her. She was profiled in a susan g. Komen video. My mom was diagnosed with cancer when she was 35 and I was 10. Reporter: But this january, at her home near houston, police say gonzalez-angulo gave the other doctor two cups of coffee, allegedly laced with a toxin ethylene glycol, the chemical commonly found in antifreeze. The lover told investigators who tipped them off, was that the coffee tasted sweet. Allegedly telling police, she knew he liked his coffee black. When he asked why it was sweet, she allegedly said, it's just splenda. Soon, blumenschein told police he was being rushed to the e.R. With slurred speech and poor balance. What would have caused a highly-respected physician to snap and do this. I think that's going to have a lot to do with how the case basically unfolds in court. Reporter: And another key part of this? That colorless, odorless chemical in antifreeze has been used before in high-profile cases. That upstate new york wife who made national headlines. Convicted of killing her second husband, poisoning him with antifreeze, suspected of killing her first husband the same way. Behind bars, castor defiant when asked how that chemical was found in both husbands. One-on-one with david muir on "20/20." Did you murder your husbands? No. I did not. I loved both of them very much. Reporter: And just like that upstate new york wife, in this new case, gonzalez-angulo flatly denies trying to kill her lover. Her attorney telling abc news, she is completely innocent. He did not discuss that chemical investigators say they found in it. This case getting attention
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