TV preview: Bancroft

STEP BY STEP: Sarah Parish as Elizabeth Bancroft, right, and Faye Marsay as Katherine Stevens in new four-part ITV crime drama Bancroft.

“She was incredibly complex and fiercely focused,” she says. “It’s quite nice playing someone that isn’t always redeemable.”

Parish has played an impressive range of roles on British TV, but it’s quite a long time since she has taken on a big lead role like Bancroft. Over the course of the four-part ITV drama, written and created by Kate Brooke, viewers will follow Elizabeth’s operation to bring down the pernicious and vicious Kamara gang.

The drama really unravels though when her colleague – ambitious recruit DS Katherine Stevens – starts working on the case of a woman called Laura, who was killed some 27 years ago.

It appeared someone, believed to be under the influence of drugs, had broken into her house, taken some of her jewellery and stabbed her violently, Parish explains. But the case was never solved.

As the investigation into Laura’s death continues, it becomes clear that Elizabeth has dark secrets of her own, and maybe she knows more about the case than she’s letting on.

Bancroft, ITV, Monday, 9pm