LINE OF DUTY, BBC1, 9pm
THE third series ended in heart-stopping, breath-taking, madly over-the-top excitement, and the fourth begins in precisely the same vein.

I loved it. You needn’t worry that moving this thrilling police drama to a Sunday night spot has softened it in any way.

Scot Martin Compston is still Detective Sergeant Steve Arnott but Thandie Newton stars as a detective trying to snare a killer. When a young woman is kidnapped off the street and then left to die in a burning house they simply trace the occupant of the property and charge him.

Job done! Easy peasy! The killer has finally been caught.

But a forensics officer, played by Jason Watkins, keeps nagging Newton’s character, DCI Roz Huntley, with questions which throw doubt on the arrest. When she curtly dismisses his worries he goes to AC-12, the anti-corruption squad, saying she might have pinned these crimes on an innocent man.

And then? Well, I’m forbidden to say more, but I can tell you things get spectacularly tense and nasty and I am so glad this series is back. Forget soppy and sentimental Sunday night dramas – Line of Duty is here.

TURKEY WITH SIMON REEVE, BBC2, 9pm
PRESIDENT Erdogan is making sure Turkey is in the news constantly, and for various unpleasant reasons, so I began watching this new travel series with gritted teeth, ready to shout at the TV if it dared show me other than shimmering seas, sunshine, and colourful markets.

Be honest, or don’t bother. And the series is indeed honest, as the title of the first episode makes clear: Gallipoli to the Syrian Border. Those two names are linked forever with war and horror, and they place their stamp on the programme even when the presenter does show us a bit of sunshine, sea and vineyards.

When he gives us the old cliché about Turkey being a land of extremes, we have to nod and agree.

With a military coup, refugees on the streets, and war on the border, the country seems in turmoil, yet can also be beautiful, peaceful and cultured, offering a home to artists, wine growers, and billionaires who glide around in their Rolls-Royces.