Jim Carter, 65
After joining a fringe theatre in Brighton in the early 1970s, Carter (right in picture) worked at the RSC and National Theatre, before moving on to TV and film. His big-screen credits include 'The Madness of King George' and 'The Golden Compass', and, since 2010, he has played Mr Carson, the butler, in the ITV drama 'Downton Abbey'. He lives in Hampstead with his wife, the actress Imelda Staunton
It was about 1980, and I'd had a very itinerant life up to that point, doing a lot of fringe theatre and travelling. I was just starting to settle when I met Steve; he and I were neighbours – I had the basement flat in a building in Maida Vale, London, and he and his then-girlfriend had the top-floor flat.
Those were the days before I met Imelda and I was a bachelor, so Steve used to take pity on me and invite me for meals. He was a genuinely funny guy with a similar sense of humour to me. He'd give me a ring and we'd go to watch rugby games at this great local pub, the Warwick Castle, where a fair few musicians would go for a few beers and sports; we were typical pub blokes: him a bit of a West Country boy and me a bit of a northern one.
He wasn't with [the folk duo] Show of Hands back then; he sang more on his own. The great thing about Steve was how he sang in his own voice; truthful and simple. With folk singers, there is a dangerously nasal twang some adopt.
As I lived in the basement flat, I had access to the block's garden and I held an annual monster bonfire night at which I, Steve and the other residents threw on any old furniture or wood that we had lying around.
After about five years Steve moved to Dorset, and so I didn't see him as much. I remember once going down to take part in a benefit gig for him – I did a few magic tricks [Carter is an accomplished circus performer and magician] and Imelda sang.
We'd been out of touch for a few years when, out of the blue, he got back in touch last year: he'd had an idea for the centenary of the First World War, setting poetry to folk music – and he asked me to read the poems.
I recorded a segment on my mobile phone [to send to producers] to generate interest for the project and both Imelda and I went down to Abbey Road with Steve and [co-founder of Show of Hands] Phil Beer and we laid down these moving First World War poems, as Steve and Phil put music to it. I think the whole experience revived the friendship. I don't have a lot of male friends, but he's one of them.
I'm a bit more extrovert than Steve, more of a showman. I'm more obvious with my jokes, while he's got a slyer sense of humour; when he makes a joke, he looks at you from the corner of his eye to check that you got it.
He does have this unfortunate habit of wearing these folksy waistcoats with collarless shirts: it's country boy rather than snappy three-piece. He'll kill me for saying this, but they do look a bit dodgy. Though it's not like I'm the smart one: if anyone wants to see Mr Carson, they're going to be a bit disappointed.
Steve Knightley, 60
A singer-songwriter, Knightley has been on the folk circuit for more than 20 years, and is one half of the acoustic roots-and-folk band Show of Hands. The duo have released more than 15 studio albums, including 2012's 'Wake the Union'. He lives with his wife and three children in Devon
In the late 1970s, Jim and I both lived in this big, rambling building in Maida Vale. I started to see him around; this big, imposing figure with this deep, slow, lugubrious Yorkshire accent. He was very dry and quite reserved.
He was in the National Theatre at the time so I went with my then-girlfriend to some of his productions in the early 1980s. He had a tremendous presence: what you get on screen is what you get off it too. We socialised at the local pub; Jim and I would watch Five Nations rugby, or he'd extol the virtues of the Yorkshire player Peter Winterbottom.
He used to do some clowning; magic, circus tricks, even tightrope walking. He has this chaotic clown alter ego; a bad-tempered drunkard, none of his tricks seem to work – which was a surprise after seeing him as this droll and dry man. And he had an amazing collection of memorabilia, tricks, circus books and clown masks; it was all slightly macabre.
A few years later, having not made my mark on the London rock'n'roll scene, I moved back to the West Country to play folk music, and our paths didn't cross for five or six years. But I watched as his career as a British character actor developed. When I put on a benefit in Dorset a few years later, he came and played his alter ego there while his wife Imelda sang soul classics; she's got an amazing voice.
I got back in touch when the Centenary project came along. He has such a distinctive voice with rich overtones that he's brought an incredible sense of Englishness to the album, and – it has to be said – the resonance of Downton and that period.
We have both risen to the top of our fields, although mine is not a mainstream genre. I rarely get a chance to watch Downton Abbey, as I'm a touring musician, but it's my wife's favourite show, which led to a great moment when I was with him recently: I rang my wife and I passed him over – she had no idea I knew a Downton Abbey actor. Now she says to me, "So you do know some famous people, you're not just a folker."
He's a very private person, so I'm not sure how much Jim relishes the publicity side of the business, while I really love it and thrive on it. I can't imagine him saying: "Don't you know who I am?" at a restaurant – and Imelda would never let him, even if he wanted to.
'Centenary: Words & Music of the Great War', with music by Show of Hands and poetry read by Jim Carter and Imelda Staunton, is out now