from Star Trek Magazine
When we were first developing the Xindi arc a year ago, over a year ago, we knew that they’d save Earth, and we used to joke around that they’d save Earth and we’d want to get back to Earth and have some twist where the crew gets home and giant cockroaches are ruling the Earth. It started as a joke, having some bizarre twist. Then, as we got closer to the end of Season 3, we realised, ‘You know, we could do something.’ We knew we had to wrap it up, but we didn’t want to end with a Xindi cliffhanger. We knew that wouldn’t be satisfying. But then we thought, ‘well, what if we throw a left turn in there? And what would it be?’ We went through a lot of different scenarios about what they would find when they got home. I can’t remember who said ‘Nazis,’ but we just somehow ended up with Nazis. Then that didn’t even feel like enough, so we made it alien Nazis. We decided to do something that would just be completely unexpected, yet give us something fun for next year, to kick off the season with something really interesting. So we took a stab at it.
The thing is that I took it for granted after a while because I got so used to the idea. I never thought it was all that surprising, but people were really shocked by it. I liked it. I know it had been done on the original series and I know we had Nazis on Voyager, but you know what? We had just done 24 dead serious, intense episodes of Enterprise. And I think that one of the things that threw people for a loop, for better or worse, was that it was a radical shift in tone to something that was wacky.