No, he's not doing a Danish travelogue. Last week BBC radio aired a new production of the award-winning play Copenhagen, about a mysterious Second World War meeting between Nobel Prize-winning physicists Neils Bohr (played by Simon Russell Beale) and Werner Heisenberg (Benedict Cumberbatch), longtime friends and colleagues who by 1941 were on opposite sides of the war. There's only two days left to listen to the program on the BBC site, but it's well worth the time.
http://www.bbc.co.uk/programmes/b01ppwn6 Also, a couple of articles about the program:
http://www.radiotimes.com/news/2013-01-11/benedict-cumberbatch-on-fame-science-and-his-new-radio-3-play-copenhagen http://blogs.montrealgazette.com/2013/01/17/cumberbabes-listen-to-benedict-cumberbatch-talk-in-a-brainy-way-about-nuclear-physics-in-the-play-copenhagen-on-bbc-radio/