'Hidden City,' 10PM ET, Travel Channel: In this 12-part series, crime novelist Marcus Sakey heads to a notable city each week and digs into controversial and juicy stories from its past. Future episodes will have him visiting Anchorage, Boston, the Florida Keys, New Orleans and other intriguing destinations, but in episode 1, he visits Chicago to delve into the grisly history of serial killer H.H. Holmes, revisits the legend of the ultimate O.G., John Dillinger, and recalls the chaos of the 1968 Democratic Convention riots.