APPLE TREE YARD, BBC1, 9pm

“BEFORE I met you I was civilised.” Emily Watson plays the sensible, respectable Dr Yvonne Carmichael in this adaptation of Louise Doughty’s best-selling novel.

At Westminster to speak to a science committee, Carmichael falls into conversation with a handsome man who has a mysterious job with the government. Soon they are engaged in a passionate affair involving high risk and exhibitionism. “Civilised”

Dr Carmichael is consumed by lust, and willing to risk her fine reputation and her marriage.

But a violent incident threatens to turn this affair from adultery into something far darker.

Emily Watson is wonderful here as the quietly frustrated Carmichael, who works dutifully in her office each day then goes home with the shopping to her nice middle-class life where nothing troubling ever happens.

It’s a life of satisfaction and peace – and that key word “civilised” – and yet we see how quickly it can all be derailed by sex.

CALL THE MIDWIFE, BBC1, 8pm

THIS drama, which is on immediately before Apple Tree Yard, is surely its polar opposite.

It’s gentle, sentimental and soppy and is something a family might watch together – just be sure to pack the children off to bed before the very sexual Apple Tree Yard comes on.

A new series starts tonight and it feels like the thousandth, though is apparently only the sixth. How many more combinations of babies, nuns and happy tears can there be?

Everyone is back in London tonight after the visit to Africa which was the setting for the Christmas special.

They arrive to find a new nun in charge of Nonnatus House and she’s rather severe and intends to put an end to nice lunches.

Away from these mildly comic scenes we step out into the harsher world where the midwives must try to help a mother who, along with her young son, has been the victim of domestic violence.

Her husband is due to be released from prison and she is in need of support.