Trigger Point season 4 has more nasty surprises in store for explosives officer Lana Washington (Vicky McClure) – including a possible betrayal from her inner circle.
The plot of the latest episodes has been kept largely under wraps, with the synopsis only giving away that London will be under threat by a group of "professional mercenaries".
In addition to explosive devices planted around the city, Lana's trusted associate DS Helen Morgan (played by Natalie Simpson) could also become a pawn in their ominous plans.
Speaking to press, co-star Simpson revealed that the character's troubled personal life compromises her in Trigger Point season 4, leaving her feeling "she doesn't know who to trust".
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"Previously, it hasn’t ended well when her personal life has got caught up in work, so she’s trying to deal with everything on her own," the actor explained.
"She’s feeling paranoid and a little bit insecure in her position, and so she makes some bad decisions along the way."
Simpson continued: "Hindsight is great, but she is living under immense stress and pressure. She just doesn't know the right thing to do."
The cryptic comments imply that Helen could become an internal threat to Lana's team in what would be a major twist for the typically trustworthy character.
But Simpson was far from disgruntled to see her character pushed into a morally questionable light – on the contrary, she was "ecstatic"!
"I kept thanking the writer, Chris Brandon," she revealed. "It made me really happy to be playing Helen as she goes through quite a confusing shift of identity.
"I've always wanted to play something like that. Helen was, so clearly, a certain kind of person when I joined the show."
Simpson teased: "She has always been such a goody two shoes, who likes to follow the rules, so it's exciting to take her somewhere different and fill in the gaps.
"I've loved exploring why she's changing and figuring out what humans are capable of... I will be really interested to see what the audience thinks of her in this series."
Trigger Point is no stranger to epic twists, often occurring early in its seasons, such as the tragic deaths of Joel Nutkins (Adrian Lester) and DCI Thom Youngblood (Mark Stanley).
Simpson implied that another earth-shattering development in that tradition is on its way, adding "suddenly... something huge happens" and "it's going to be a shock".
At that point, she was in a love triangle with Thom and Lana which ended in tragedy, with the iciness between herself and McClure's character taking time to thaw.
Brandon concluded: "It's about engendering a little bit of distrust within the unit itself, which takes us in some really enthralling directions."
However, the prolific TV maker recently acknowledged criticism from real-life members of the police force, on his perceived downplaying of the unity and teamwork they strive for.
In addition to McClure and Simpson, the Trigger Point season 4 cast also includes Eric Shango, Maanuv Thiara and Nabil Elouahabi, plus newcomers Julie Graham (This City is Ours) and Jonas Armstrong (After the Flood).
Trigger Point season 4 premieres on ITV1 and ITVX on Sunday 30 August 2026.
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