We’ve seen child star Thomas Sangster acting in films for years, so we wanted to find out how he felt being only a ‘voice’ in his new film Phineas and Ferb: Across the 2nd Dimension.

Can you tell us about the film?

It’s basically a feature-length version of the TV show Phineas and Ferb, but on a much more grand scale. It gives a lot more time for our characters to really go full pelt and have a proper adventure.

What is your character like?

My character is the step-brother of Phineas – he is a very quiet character and he doesn’t really say much, but there is a lot going on. He is the practical one who builds all the machines that Phineas’ mind creates.

Are there any similarities between you and Ferb?

I’m pretty quiet. I don’t really speak unless I have something useful to say, which is what Ferb does. I think I am kind of the same.

How different is just using your voice to acting a part in a film?

When I first started doing it, it was kind of hard. I wasn’t used to purely acting with my voice and everything has to be amped up a lot more. You have to put energy into your voice and if you did that on camera, it would be way too over the top!

Have you always wanted to play a cartoon character?

Not particularly, but I always thought it would be quite a cool thing to do!

Are you a big fan of cartoons or do you prefer watching actors?

Both, really. Film is wonderful, but animation is also great, especially sometimes it can be easy to watch and you don’t have to think too much. It’s all visual and fun and I think sometimes you need that as a relief. Sometimes you just want to sit back and get taken away to a fantasy world and cartoons are great at doing that.

Do you wear anything special to get you into the mind of Ferb?

Well they showed me one picture of what my character looked like and I don’t have anything in my wardrobe that looks like what Ferb would wear. I just went in being me and that is basically what I am in the cartoon. I don’t really put on a voice, I just make sure I sound a bit more posh.

Did you have any voice training?

No, not at all. The guys I work with in the studio helped me a lot because they know what they’re doing and were able to guide me. Apart from that I just learnt as I went along.

Did you get on well with other members of the cast?

Yes I think so, but I haven’t even met them all yet. I am one of the only actors on this side of the Atlantic, so it’s quite bizarre. We never really meet up.

So did you stay in England to make this film?

Yes, I stayed at home in London.

How do you stay in touch with your friends?

They are kind of used to my situation. I can be at home for a very long time and then suddenly I will get a call and be off for a certain amount of time. I am not very good at keeping in contact with people. I know I am only there for a certain amount of time and I try and enjoy that time. I hang out with all the cast members and the crew and make the most of it, because then it’s over!

What’s been your favourite character to play?

I can’t say, they all have something special about them – they are loosely based on me really. There is always a part of me inside each character.

So what else do you have lined up?

I have just come back from Toronto Film Festival promoting a film called The Death of a Superhero and another film is being edited at the moment.

Have you been on holiday this summer?

Well, I have been to a few places with work, but I don’t really count them as work because I love my job. But I haven’t been away on a proper holiday in years!

Phineas and Ferb: Across the 2nd Dimension is on tonight (Friday 30) on the Disney Channel at 6pm and is on again on Disney XD on Thursday 6 October at 5:30pm.