Suspect star addresses big unanswered question in season 2: 'It's fantastic drama'

"It means that you can have that ongoing for the next season, that's the next story that's coming," said Nicholas Pinnock, who plays an ex-marine called Joseph who is a former patient of Susannah's (Anne-Marie Duff).

"Instead of it being just one person, you've got this organisation, so you have to find where the head is and cut that off. That takes a lot of chopping through the body to get there, and that keeps you gripped, it keeps you hooked."

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In season 2, it emerged that returning character Detective Inspector Richard Groves (Ben Miller) was seemingly on the payroll of the nefarious force behind the killings, although the reasons for that have yet to be made clear.

"There's a bit more to it this time," said Miller of Grove's development ahead of the show's release.

"In season 1, it was kind of hard to figure out exactly where Richard stood in all of this. In this season, it's become a little more developed. You find out a little bit more about him, and... I really like it."

He went on to say that while Groves is an unremarkable character on the surface, he has an "underlying ambiguity" that drew him in.

"What I find fascinating about him as a character is he's one of those people that you wouldn't spot in a crowd," said Miller. "You know, it's a kind of important thing, really – a certain kind of person who fades into the background.

"So it's interesting. It's like putting a spotlight on the sort of person who wouldn’t go anywhere near the spotlight, usually. And I find that aspect of my character interesting.

"For me, it’s the underlying ambiguity – he's a character with his heart in the right place and yet he's a suspect like all of the characters."

Suspect seasons 1 and 2 are available to stream now on Channel 4.

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