Look at Nicola Walker in 'Last Tango in Halifax.' She has the most wonderful face. You just want to look at her. And if she'd gone off and had Botox and facelifts, I wouldn't want to look at that face because it wouldn't express anything.

Nowadays, people send rockets into space, and I think it does make you question if there's a God. They can make babies in a dish now! Everything we're seeing goes against what people always believed in.

Because 'Call The Midwife' is a gentle drama, not a documentary, it's not appropriate to portray Sister Monica Joan's condition in all its brutal reality.

I don't know if a penny's dropped somewhere, but you've had 'Lark Rise to Candleford,' you've had 'Cranford,' you've had 'Last Tango in Halifax,' you've had 'Call the Midwife'... I think the largest portion of the viewing public are over 55, and they like to see people they can identify with.

That's the thing with dementia. If you're with somebody who has a serious illness, you can usually talk to them, have a laugh every now and then - the person is still with you. With dementia, there's no conversation; there's no togetherness, no sharing.