What's the story?

Shetland.

It's back?

Affirmative. The popular BBC Scotland drama returns for a sixth series this week.

Tell me more.

DI Jimmy Perez is home on Fair Isle to attend his mother's funeral (a poignant opening scene that will bring a lump to the throat) when he gets a call to say he's urgently needed back at base in Lerwick.

The Herald: Steven Robertson, Alison O'Donnell and Douglas Henshall in BBC Scotland drama Shetland. Picture: Mark Mainz/ITV Studios/Silverprint/BBCSteven Robertson, Alison O'Donnell and Douglas Henshall in BBC Scotland drama Shetland. Picture: Mark Mainz/ITV Studios/Silverprint/BBC

There's been a murder?

You guessed it. A prominent local figure has been shot dead in broad daylight.

Any suspects?

A list as long as your arm. The victim has no shortage of enemies.

Who is in the cast?

All the usual gang. There is Douglas Henshall, Alison O'Donnell and Steven Robertson as our intrepid crime-fighting trio of Perez, Tosh and Sandy. Mark Bonnar plays Duncan Hunter with Neve McIntosh as Kate Kilmuir.

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Stephen McCole – who starred with Henshall in Orphans back in 1998 – joins the cast as brooding war veteran Logan Creggan, with Kate Bracken as troubled addict Lynda Morton. The stellar line-up also includes Jim Sturgeon, Cora Bissett, Alec Newman and Lois Chimimba.

Anything else?

A polarising storyline. The compassionate release of murderer, Donna Killick, played by Fiona Bell, leaves many of the islanders aggrieved, not least Kate Kilmuir – the victim's sister.

When can I watch?

Shetland returns to BBC One, Wednesday, 9pm.