Joan Collins’ . The porcelain doll-like pin up. Black-linered lips around a cocktail cigarette and sucked in high-boned cheeks. The many-surgeried, heavily caked face that is the mask of the fabulous older woman. Joan Collins’ face has been in my consciousness for most of my life. I first saw it in the first episode of the second season of Dynasty. The character of Alexis is famously introduced in the closing moments of the cliff hanger of the first season when Fallon utters the immortal line, ‘My god: that’s my mother’. Only we don’t really see her mother’s face. It’s hidden by big dark glasses, a wide-brimmed hat and veil. And the reason for that was that Alexis wasn’t cast yet.…