'I looked like a baby as Liam Neeson's stepson in Love Actually, but it's nice that people say I did a good job in it'
It may be nearly 14 years since Love Actually was released, but actor Thomas Brodie-Sangster still gets recognised for the role he played as a 13-year-old alongside Liam Neeson.
Thomas Brodie-Sangster knows exactly what to expect every Christmas. TV channels will replay Love Actually, in which the actor - then just 13 years old - played Liam Neeson's step-son Sam.
"I do still catch it on TV every now and again and go, 'Gosh that really was a long time ago'," says the 27-year-old. "I looked like a baby."
The former child star has built up a varied CV following his role in the Richard Curtis rom-com, most notably as Jojen Reed in HBO's gritty fantasy drama Game Of Thrones, and he is now back voicing his "childhood idol" John Tracy in Season 2, Part 2 of Thunderbirds Are Go on CITV.
"Everyone knows the characters by now, so it's quite nice how we can kind of zoom between stories," Brodie-Sangster says.
"It's always been fun. A lot of the guys who play my brothers; they're all huge fans of it too, so we all kind of turn to each other and say 'ah, this is exciting'."
Thunderbirds enthusiast Brodie-Sangster, who was introduced to the show when it was remade in the Nineties (and yes, he owned all the toys), reckons one reason the story of Tracy Island has stood the test of time is because it's centred around family.
"There's a cool, gung-ho, adventurous attitude mixed with a general love and care for one another, which is a nice trait to have and they're good things to promote to young and old people," he says.
But how did the London-born actor find working solely in a recording booth?
"You've only got your voice to work with, you have to put all of your character into just your voice, which is interesting and challenging and fun and different," he remarks.
"And the pace of it is so different to filming as well - you can get through two episodes in a day and that's just impossible in film.
"It's nice to mix it up and push yourself in different ways."
While the actor has taken on such a wide range of roles since his turn in Love Actually, Brodie-Sangster admits the film is still what he gets recognised for the most. Does that get annoying?
"You can't be d***ish about it, you have to accept the compliment and think that it's a nice thing for someone to actually point out that you did a good job at something," he states matter-of-factly.
"It can be distracting and it can be frustrating sometimes, but it's just one of those things that you have to deal with."
Plus, it turns out the keen musician got more from the role of Sam than just his first taste of fame.
"I did actually learn to play the drums for it," reveals Brodie-Sangster, whose Love Actually character quickly masters the instrument to impress his crush Joanna at their school Christmas concert.
"My dad's a drummer and he taught me in my grandad's basement, bashing away on his old kit and trying to play along to All I Want For Christmas.
"It got very tiresome very quickly for anyone who was in the room, but on the day we were shooting, I was like 'Oh yeah, I get it now'."
All this acting experience must have been pretty exciting, but does he ever just wish he had a normal childhood?
He says: "I'd say I think it was good for me.
"School never really excited me that much. I found it very frustrating. Basically all they do is teach you things on a curriculum and then you pass a test in order for you to move on to the next stage of your education.
"I just found that I was learning a lot more from working in a professional atmosphere and working with people and talking to people and portraying characters."
However, he doesn't shy away from admitting that working as an actor meant he didn't get to spend much time with kids his own age.
"All my conversations were different, so sometimes going back to school was a bit of a shock," the star confides.
"As a teenager as well, when everyone was into parties, and part of puberty and that awakening and everyone was kind of finding themselves, I guess I kind of missed out on that and I wondered whether I'd missed out in a negative way.
"But I don't feel I have."
And when it comes to future roles in his career, the level-headed actor insists he has never felt any pressure to get a certain job.
"I just get the ones that appeal to me as a character, that I can do justice to and do a good job at," he says, after revealing he did not even know what Game Of Thrones was when he landed the role.
"But it's nice when you read something and think 'I never expected to play that kind of character'.
"That's part of what's lovely about it - you don't know what's going to excite you."
- International Thunderbirds Day is on Saturday with Season 2, Part 2 of Thunderbirds Are Go coming to CITV the same day at 8.30am