Doctor Who launched my acting career. I was in this awful transitional period, going from singing to acting, so getting the part of Rose Tyler felt like a real vote of confidence. I'm not sure the fans were as happy - loads seemed hacked off, as they often are about change - but they soon seemed to accept me.
I've signed quite a few fans' bodies over the years, but my fan mail has been very gentle: these are smart people, with sci-fi intellects.
At first I didn't know whether the show was going to be a success or die a death, It was such a hard shoot: nine months, with pretty much everyone using CGI for the first time. There were times when I thought, "Is this ever going to pay off?" But it did.
I remember being in a London hotel for the launch of the first episode. There was such a buzz; it was thrilling. I called a friend and said; "I'm going to remember this for the rest of my life".
I loved the character of Rose; the fact that she was a girl who went from a small, domestic life to experiencing time travel with this strange guy. She was both strong-willed and vulnerable. I think that's a really healthy representation of women. Instead of showing a female character endlessly striving towards perfection, here we have a range of genuine female reactions. The show seemed to say, it's OK to cry, it's OK to question yourself, and it's OK to get excited about someone else coming up with a great idea.
I've had some discussions recently with a friend who is convinced the next Doctor needs to be a woman. I don't think he does. I like that he's a man and he has his little time-travelling mate. You see what's important in that kind of relationship: what a man can offer, what a woman can offer. It's OK to feel small against this enormous male character. It's actually quite romantic.
Taken from The Weekend Guardian Magazine. Available today.