To celebrate the show's return, we grilled Martin on his television likes and dislikes for TV Heaven & Hell - read on for his thoughts on Antiques Roadshow, River Cottage and starring in a remake of classic sitcom Porridge!
How are you feeling about the success of PhoneShop?
"Obviously, I'm really pleased with the success. The love on the street is extraordinary - people seem to love the characters. I think [the show] had a slightly bumpy start, with people not quite getting it. They sort of thought that maybe it was [trying to be] a bit cool, but actually it's not. We're all pr*cks really!
"It's just a traditional sitcom, really, if you strip it down. But it's been an immense success, yes. I'm really over the moon with it, to be honest."
What can we expect from series two?
"I can't really give too much away! Suffice to say that Jerwayne (Javone Prince) has a massive issue with an ex-girlfriend and my character Lance has his usual problems with his wife Shelley (Juliet Cowan) - her being a bit of a nightmare!
"And I can say that we do go out of the shop a little bit more. The first series was quite heavily based in the shop and I think Phil Bowker - who writes, produces and directs it - was keen to anchor it, to give it a grounding in the shop so that people understood where these characters were coming from. [But] now we go out of the shop a little bit more."
Is it true that the cast contribute material to each episode?
"Yes, we do. We workshop it in a windowless basement at Talkback Thames! That's months before [filming]. So Phil will come with a not quite fully formed script, and then we improvise around it and come up with dialogue. We also come up with the odd plotline as well. So we do have a very reasonable input into the scripts.
"But on set, we've kind of done all the improvising and that's gone into the script. So on set, we don't really improvise that much. Just a little bit. It might look like we're improvising, but actually it is mainly scripted already."
"Really sad, really sad. It was a gravy train that's pulled into the sidings! I was really sad to see that go. When we started on it, as an actor, you just go 'This is great, I've got a job!' It was a great part, and I was actually there on the first day of filming, for the first scene.
"You just think, 'This is six weeks work, lovely!' And then you get a second series [and so on]! The first series didn't really go that big, to be honest. But with the second series, people really latched onto it and it just exploded. You never know that's going to happen - I've done other things that have been really good and have died on their arse!"
What TV show are you loving at the moment?
"I'll tell you what I love is [Channel 4 drama] Top Boy - I think that's absolutely fantastic. That's superb telly - beautifully shot, beautifully written and I think the performances are excellent."
What's your favourite ever comedy?
"It's probably going to be Seinfeld - that's one of my favourites. Although I like Family Guy as well - I'm a big fan of that."
What's your idea of TV hell?
"I've never watched an episode of Coronation Street - I wouldn't say I don't like it, but I've literally never watched it. [It] doesn't really appeal.
Did you have a favourite TV show as a kid?
"I liked The Young Ones when I was young, but as a real kid, it had to be Scooby Doo. It's still going - they're still making new episodes, but not with the right voices obviously! I've always been a big fans of cartoons - I love [Looney Tunes character] Foghorn Leghorn, he makes me laugh! I watch them with my 4-year-old online."
Do you have a TV guilty pleasure?
"I quite like cookery shows. MasterChef is a slight guilty pleasure, and Jamie Oliver. I really like River Cottage - it's like having a warm bath!"
If you could appear in one TV show - past or present - which would you pick?
"Porridge, probably. I just think that Ronnie Barker's part in that was just fantastic. I used to watch that with my Dad when I was quite young. It was just such a superb character and [Barker] did it so beautifully. I would probably never do it justice, but I would've loved to have played that part."
So you'd be up for starring in a Porridge remake?
"I'd f**king love to! I'd love to, yeah!"
PhoneShop returns to E4 on Thursday at 10pm.