Vera's Brenda Blethyn 'was quaking' over visit from author and creator Ann Cleeves

The Kent-born actress, 73, had to perfect a different dialect when she took on the role of DCI Vera Stanhope in the Northumberland-set crime drama.

She told Radio Times magazine she was terrified when she heard that Cleeves - who penned the novels the ITV series is based on - was coming to hear her read the script.

She said: "I was quaking in my shoes when I heard Ann was going to be at the first read-through. 'Oh Lord,' I thought.

"She was probably terribly nervous as well because it was the first book she'd had televised.

"Ann thought my accent was a bit off, but it got better the less nervous I got. And so by the end of the read-through, she was happy."

The actress has been playing the detective since 2011 and said some locals now think she is a Geordie when they are filming.

She said: "Vera's accent was inspired by the soft, musical lilt of Denise Robertson, the late TV agony aunt from ITV's This Morning. It couldn't be strong because if you miss anything, you'll lose track of the plot.

"Any criticism that I get is generally from southerners who expect a broader accent. In fact, some locals think I'm a Geordie, which is a great compliment."

Vera is returning for a 10th series later this month.