MI-13, sometimes written MI13 or MI: 13, is a fictional British intelligence agency appearing in American comic books published by Marvel Comics. MI-13 is depicted as operating out of Portwell House in Whitehall. It was introduced in Excalibur vol. 1 #101, by Warren Ellis under the call sign "The Department" for ten years until New Excalibur #1 explicitly mentioned the term "MI13"; although invariably referred to as such, the agency's official name is the Extraordinary Intelligence Service (EIS).