Having polished off the Hugos a couple of months ago, I'm getting started on those Nebula winners I have not previously written up online. Man Plus is mostly a horror story about a man who is turned into a cyborg in order to explore Mars, but Pohl overlays it with a couple of other themes. First, he has a near-future projection of the political paranoia of the 1960s and 70s at both US and international level, a very cynical portrayal of how things work at the top which is I guess reflective of the post-Watergate era. Second, he has the secret manipulators of human politics, who gradually take form as first-person narrators as the story goes on, which runs the risk of being actually a bit twee and clichéd until we get the sting on the last page. So it's an impressive combination of themes; shame about the women characters, though.