Chicago’s very own Mayor Rahm Emanuel will take a moment off today to film a late night interview on the Late Show with David Letterman. The mayor is supposed to be flying into New York to film the interview then head right back to Chicago later on tonight according to mayoral spokeswoman Sarah Hamilton. For those wondering why in the world a Chicago mayor will be going to New York for an interview, it’s supposed to be in support of the release of a Discovery Channel documentary about presidential chiefs of staff that will air in two parts on September 11 and 12. Titled “The Presidents’ Gatekeeper,” Emanuel is sure to be featured in his role as President Obama’s chief of staff. And in case you’re curious, Ricky Gervais and Janelle Monae will join the mayor on Letterman.