I don't know about the viewing figures in comparison and I don't think a 12 hour "24" can exactly even be compared to the usual length one but, "24" was done really, just Kiefer Sutherland wanting to do more and a film, but the last series - re-located to London - is supposed to have re-kindled interest and now there are stirrings about brining it back, sans Kiefer, but that's not exactly a like for like comparison with "Legends", and Americans seem to like London, not so sure how they will feel about Prague though.