THE SECRET, STV, 9pm

TV WRITING is a job like any other.

I do my work then I get on with something else, as we all do. But there was no “clocking off” with this new drama. I watched the first episode and then went straight on to the next one.

The Secret is a four-part drama based on a true story. The facts are out there (just google “Colin Howell”), so the plot is not the clincher. Instead it’s about evoking poisonous atmospheres of helplessness, desperation and ruinous lust.

James Nesbitt plays Howell, a religious family man living in small-town Northern Ireland. He starts an affair with Hazel, a married woman from his church. They know it’s a sin but justify it by saying such a splendid thing must be God’s will.

When they’re discovered, they find they can’t return to separate lives of dull domesticity. They are furiously set on being together and yet divorce is not an option.

Perhaps murder is?

TWO DOORS DOWN, BBC2, 10pm

CHRISTINE is telling her daughter that breast-feeding is no easy task: “Every time ah opened ma nightie ye screamed the place doon!”

“I must have got that off my Dad,” snaps Sophie.

The two are bickering as Christine tries to discover who the father of Sophie’s baby is. She goes through the names of every local man and his brother before locking her daughter in the shed – and battering it with her walking stick – until she confesses.

With this domestic strife going on, Cathy plays peacemaker. Now that she’s in therapy she believes she has a deep understanding of human behaviour. However, her therapist has advised she cut out all stimulants, so she’s on the boring old decaf, which tastes a bit funny, she finds, unless she tops it up with a slug of Bailey’s.

With this, and STV’s The Secret, I’m baffled to report that Friday night TV is actually good.