Are you phobic towards small animals?

No, I love small furry animals. You should see my dogs, they're all small furry creatures, except for the two that aren't small or furry.

I had always been fascinated by the whole idea that Australia was this different ecology and that when rabbits and prickly pears and other things from Europe were introduced into Australia they ran amok. I always thought this was a remarkable story about the law of unintended consequences, so I thought, "What if you could have rabbits or mice [in a story]."

The girl I was seeing at the time had a little fuzz ball on the end of her key chain and I thought, "What if you had little fuzz balls that bred like crazy," and the next thing it was like, "Yes that's obvious because all we have to do is get little fuzz balls off the key chains, we'll go and buy five hundred key chains."

Actually we didn't do it that way, but that was where the idea came from. Essentially, it's what if you had rats on the space ship - where do you go from there? And it turned out to be a lot of fun.

I think for me the most fun was that I would visit the set and for the actors it was the first time they had really had the chance to do a show that was a comedy. They were just having a party. Everybody was having an enormous amount of fun, especially William Shatner who's normally a very funny man.

I think this was one of the first chances he'd ever gotten to do a comedy of any kind. Previously he'd done a couple of Twilight Zone episodes where he'd done the very intense guy who sees the thing on the wing, the gremlin on the wing of aeroplanes, stuff like that. He'd done an episode of Thriller where there was this painting that was hacking people to death.

He was only doing dramatic parts and I know he loved the opportunity to do comedy, so for him this was a chance to break out. I think it's part of the reason people look at him as a comic actor today, where he can do things like Miss Congeniality. Last time I spoke to him he said he loved doing the comedy.