As an editor at Scientific American John Rennie delighted in the weird correspondence they received, but then one letter crossed a line.

John Rennie is a science writer, editor, and lecturer based in New York. Viewers of The Weather Channel know him as the host of the original series Hacking The Planet and co-host of the hit special The Truth About Twisters. He is also the editorial director of science for McGraw-Hill Education, overseeing its highly respected AccessScience online reference and the McGraw-Hill Encyclopedia of Science & Technology. Rennie served as editor in chief of Scientific American (including the monthly magazine, Scientific American Mind, ScientificAmerican.com and other publications) between 1994 and 2009.

This story originally aired on September 26, 2014.