Vicky McClure

If you have a passion and love for something, it's hard to give it up. I had jobs where the people were helpful and let me go to auditions, and I'd make up the hours another day. I was lucky in that respect: I could afford to get to London.

Madonna remains the most visible performer on the planet, as well as one of the wealthiest, but would anyone seriously say that artistic self-development is her primary motivating principle? She is too busy with Kabbalah, fashion merchandising, adoption melodramas, the gym, and ill-starred horseback riding to study art.