After the Flood's Sophie Rundle says Jill Halfpenny's character is "not quite right" – teasing "devastating" moment

Alongside several returning faces – including lead Sophie Rundle – After the Flood introduces a number of new additions in season 2, among them Jill Halfpenny.

Halfpenny plays DS Sam Bradley, who has recently relocated to the fictional town of Waterside from Newcastle after, according to her official character description, "finding herself single and home alone now that both of her kids are at university".

On paper, Bradley sounds like an ideal fit for the team, described as "a highly qualified and experienced murder detective".

"She's pretty calm – she knows her stuff," Halfpenny told RadioTimes.com and other press. "She's been around for a long time, and she's been brought in because she's worked on these kinds of cases before. She's a steady presence."

And that's certainly a quality she'll need, given what Jo and her colleagues are faced with in season 2.

"As tensions simmer in Waterside amid the rising threat of moorland fires and the subsequent risk of further flooding, a body is discovered in bizarre circumstances," reads the official synopsis.

Jo's race to catch the killer soon "brings her into direct conflict with powerful and influential forces within the town", ultimately drawing her into an investigation that becomes deeply personal.

However, while DS Bradley makes a positive first impression, Rundle has teased that there's "something not quite right" about her – hinting at a "devastating" development in the closing stages of the thriller.

"There's a big old bang at the end of the series," Rundle said, adding that she was "too nervous to talk about it", having not yet filmed that scene at the time.

"I really hope it'll be one of those big, 'gasp – they did that? I can't believe they did that' moments."

Season 2 also sees Jo and Pat (Matt Stokoe) – now separated after she discovered he had been "on the take" for years – quietly plotting against Mackie, while continuing to successfully co-parent their daughter.

Nicholas Gleaves's character, who had become a surrogate father figure to Jo following the death of her own dad, was unmasked in season 1 as both a corrupt police officer – Jo's father had also bent the rules during his time on the force – and a murderer, leaving her horrified.

If you need a refresher, we've broken it all down in our handy ending explained.

"Jo and Pat are saying, 'Everything’s fine. Don't worry about it,'" Rundle explained. "But we were left wondering, 'Are they going to bring him down? Are they going to blow the whistle?' They're pretending everything is fine so they can build a case against him and buy themselves some time."

"But he’s not stupid," she continued. "He's very aware. There are lots of forced smiles, and that's so uncomfortable for Jo because she's the kind of person who just can't leave things alone. She might have an easier life if she could – but she can't.

"And whenever he interacts with her daughter, it just makes her feel sick. So the momentum is building, and I think there's a time limit on how much Jo can stand – and how long Mackie will believe that everything is fine."

Lorraine Ashbourne also returns for season 2 as Jo's mum Molly, now a councillor, alongside Philip Glenister as Jack, a property developer who lost his entire business in season 1 and has long held a torch for Molly.

Jacqueline Boatswain also reprises her role as Sarah, an MP and Mackie's wife, who was having an affair with Jack.

Additional new cast members include Ian Puleston-Davies (Coronation Street, DI Ray), Alun Armstrong (Breeders, Sherwood) and Matthew McNulty (The Jetty, The Rising).

After the Flood season 1 is available to stream now on ITVX.

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