"It's the funny thing about the film industry. They're constantly forgetting about certain huge audiences. They completely forgot about teenage girls for a while; then 'Titanic' came out and made something like 3 billion pounds - basically from teenage girls.
"Before that, I remember they forgot about [young] kids. In this case, they forgot about the baby-boomer generation, which is an awful lot of people who are now in their 50s and 60s, and grew up on the cinema. They've got money in their pockets, they're free of having to go home to look after the children, and they want to go to the movies," she said.
"It's not actually that straightforward to make a successful one. You've got to get the balance right: the right amount of wit, of laughs, of action, of characters - real, interesting characters, not just cliches. Ou need quite a magical little concoction to make the thing fly rather than just sit there and be ignored.
"But I think with a bit of genius casting in the first one, and some funny lines, the piece worked... Yes, the piece worked. So it was great fun to go back to it.