Phil plays Harry Venn, a womanising solicitor who must face up to some ghosts from his past when he encounters the enigmatic Gina, played by In Bruges star Thekla Reuten. Digital Spy and a bunch of other journalists caught up with the actor to chat about his new role, the spectre of Gene Hunt and how it felt to be on the wrong side of an interrogation table...
What can you tell us about Hidden?
"It's a four-part new drama - sort of a conspiracy thriller, written by Ronan Bennett. I play a guy called Harry Venn, who we think is just an ordinary high-street solicitor.
"But as the story progresses, we find out that he's got a bit of a shady past which catches up with him, by means of a character called Gina (Thekla Reuten). She comes into his life to impart some information which embroils them in this heavy conspiratorial thriller."
Is Harry a bit of a dodgy character?
"He's had a past, [but] he's not dodgy, no. He was involved in a botched house raid with his brother - Harry was the getaway driver, when he was about 18. We have some flashbacks where you see that - obviously not with me! It's not me in a dodgy wig!
"I gave a picture of me when I was about 18 or 19 to the casting director and they went from that, trying to find somebody. You see the guy they found fairly clearly in flashbacks, so you just have to buy it and believe it.
"In the process [of this raid], his brother was shot and killed. He's lived with that for a very long time, and it's created a very tense relationship with his father, who blames Harry in many respects. Harry's now turned out to not be a very good father to his own son, who's heading off on the wrong tracks as well, so he's got a few issues going on in his life."
With Harry as a lone investigator, does Hidden have a film noir feel?
"Yeah, and I think that was something very particular that they wanted to do, in terms of the style. We had a Swedish director of photography, so that explains that! He thought he was [Ingmar] Bergman! But it sort of works - I like the look of it. It's got that feel of something like [the Danish version of] The Killing or one of those European shows."
What was it about Hidden that appealed to you?
"The whole package appealed, really, the whole piece. When I get a script sent to me, I read it and if it's not to my liking, I pass it over to the kids for drawing paper! And if I like it, it stays as Daddy's drawing paper! And this was very much Daddy's drawing paper.
"They approached me about putting my name to it and I was told that Ronan had written it, and David Thompson was producing it. I went and met them, then read the first episode. I got to the end of the first one and immediately I wanted episode two. That's always a good sign, when you want to continue with the story."
After Life on Mars and Ashes to Ashes, were you sent a lot of scripts in that mould?
"No, actually. Funnily enough, most of what I got sent was comedy stuff. Which was fine, but it just wasn't right for me. It just didn't feel like the right sort of thing and it wasn't a route that I was particularly interested in. It wasn't something that was playing to my strengths either and it's something that I think I would have struggled with."
Would you like to star in a comedy?
"Oh yeah, absolutely, but it's got to be something more like comedy-drama."
Did you plan to take a break from television after Ashes to Ashes?
"It was just a question of biding my time, being patient, and waiting for something that I thought was the right thing. Not just rushing in and thinking 'S**t, I'd better take that' - having the confidence and the belief to sit tight and wait for something that was right. Fortunately, it was this."
Are you a fan of conspiracy thrillers?
"Oh yeah. We'd had a lot of them [recently] and I think they've all been very, very good. I think what it boils down to is, I just like a good story and something that engages you. Something that's a little bit different and a little bit grown-up, if you like.
"I loved The Shadow Line - I thought that was fantastic and really bold and brave. Hugo [Blick] wrote, directed and produced it - f**king amazing! It wasn't everybody's cup of tea, I'm sure, but I just thought it was brilliant."
Do you get many action hero moments in Hidden?
"Not that many actually! I'm on the wrong side of the interrogation table in this one, which was a bit confusing. Being throwing around a room, I thought 'Hang on, I'm the one who does the throwing around!'."
And is there any romance?
"For Harry? Might be! He still holds a bit of a candle for his ex-wife and although she's kicked him out, they're still on speaking terms. It's almost too amicable and you wonder why they split. But they have their moments still!"
"Yeah. It's weird. I was in Majorca when the riots kicked off and it was just quite strange. I only watched the first ep of Hidden about two weeks ago, with all the TV reports put in about the riots. I'd sort of forgotten about that and suddenly it was like, 'S**t, that's quite prevalent'. Maybe we're psychic, who knows?"
Going back to Life on Mars and Ashes to Ashes - would you like to play Gene Hunt again?
"It's a tough one, because it was a great part and I loved playing him. Part of me says I'd love to play him again, but in the real scheme of things, I think we've left it now, it's been done, and if we went back to it, it wouldn't be anywhere near as powerful. So I can't see it happening, no."
How did you feel about Harvey Keitel playing Gene in the US Life on Mars remake?
"Interesting! I didn't really see much of the American one, but I spoke to him on the phone. I had no idea he was playing the part. The phone goes and it's Harvey Keitel.
"The first thing he says is 'Phil, you bastard, this is Harvey Keitel, and you played this f**kin' part too good, ya f**k. How am I going to play this, you f**king bastard?'. I was like, 'You're Harvey Keitel, you'll be fine!'."
Did you hear how the US Life on Mars ended? Sam Tyler was revealed to be an astronaut heading to Mars...
"Yeah, we did see the end. We were shooting the last series of Ashes and Dean [Andrews] had seen it and downloaded it. He said, 'You've got to come and see this, it's just terrible. It's a Gene Hunt - a hunt for genes'. I said 'You what?!'. We watched it, and it was just like, 'What the f**k?!'."
Hidden begins this Thursday at 9pm on BBC One.