Sports broadcaster Eoin O'Callaghan learned his trade as a television researcher before moving into broadcasting with RTE Radio. A move across the Atlantic opened doors for the young Corkonian and he soon found himself covering the 2010 Winter Olympics and reporting on European football for the Fox Soccer Report. After contacting Canadian actor Jay Baruchel about an idea for a documentary, he was amazed when he agreed to do it. Here's how Celtic Soul made it to the screen.

Firstly, what's your background and how did you end up working for Fox in Canada?

I started in RTE while I was still studying Communications in DCU. My first role was as a researcher in the TV Sport department and I worked across all of their football output which, at the time, was a really sizeable portfolio: the odd live Premier League game on a Saturday, 90-minute highlights show every Saturday night, Tuesday & Wednesday Champions League nights and every Republic of Ireland international. It was a dream job for me but I wanted to get involved in broadcasting so I began to veer into radio. I did Radio 1 and 2FM sports bulletins, covered League of Ireland games on freezing Friday nights and contributed to various shows.

In 2009, myself and my missus decided to see a different part of the world for 12 months and so we headed for Vancouver. It dovetailed nicely with the 2010 Winter Olympics being held there and I covered it locally and provided reports for RTE and BBC too.

Every night, I watched a TV show called Fox Soccer Report - an hour-long studio production that carried main news stories of the day and highlights from leagues around the world. I felt it was right up my street and sent examples of my stuff to the execs in charge. In May 2010, I got a call from them asking if I could start in time for that summer's World Cup. So, from there, it happened very quickly. It was my boyhood dream and the show was broadcast right across North America & the Caribbean. I'd get texts from friends or family who'd be in a sports bar in NYC or Washington and be completely freaked out that my ugly mug was on 15 different screens simultaneously while they were trying to enjoy a drink and some food.

We see you meeting, but at what point was Celtic Soul envisioned? Did Jay casually mention he was a Celtic fan?

Noel Gallagher always talks about 'going fishing', in terms of songwriting. Sometimes something bites & after a bit of thrashing around, you settle down and go through the process. I've always been coming up with various documentary ideas but ideas are worthless if you can't execute them. Sometimes, I'd use ideas in different ways - borrow from a TV pitch for a written feature or vice versa. And in 2013, I was piecing something together about the centenary of World War I and successful athletes with interesting stories who perished on the front. I liked the angle of being born in a different country but fighting for another flag. There were some Celtic examples of that, mainly linked to Canada & the British Army. And that was the germ of the idea - Celtic, Canada, emigration - but done through the prism of sport. I spent a lot of time at my kitchen table in Crumlin in 2013 knee-deep in research, basically.

When Jay and I started to message each other, it just mushroomed into something a bit different. I knew he was a Celtic fan already but he's also a history nerd. And I liked the idea of a contemporary look at Celtic through the eyes of an outsider. When he mentioned his family tree, how proud he was of his Irish background and how he'd devoted hours and hours of time to walking around Westport via Google Maps to see where John and Thomas O'Malley - his ancestors who left for Canada in 1842 - lived, that was the light-bulb moment. We then could use Celtic and Jay's journey to Glasgow as a metaphor for everything else, essentially because the origins of Celtic - a club built as a safe haven for those who needed help and support - is the story of Jay's family. And the story of emigrants everywhere, I guess. So, you keep that contemporary angle also.

When you talked about your vision for the doc, is the end product close to what you imagined?

My initial plan had Jay doing this all on his own. My original pitch was a four-part series, actually and I felt this was his journey and the thought of featuring in it myself never crossed my mind. Until Markham Street Films in Toronto - who I was introduced to via a mutual friend and who subsequently invested so much in this project - suggested it in a Skype call. They felt our own story of getting together was pretty funny - following each other on Twitter, the Skype calls, etc - and that it was worth exploring. So, that was certainly the biggest difference in terms of the initial idea and what it morphed into. But, I'm a huge fan of The Trip - well, the first one, at least - and I felt that if we had chemistry and this wasn't a pious, preachy thing, it could be okay. But I was nervous as hell before we started filming in Montreal. Like, every second week you're flicking through channels and Knocked Up or Tropic Thunder or She's Out Of My League is on.

Some of the best moments are just you guys shooting the shit in the car. How much did you have to cut out?

I still feel really bad for our director Michael McNamara and our editors who had to listen through hours and hours of the worst, most boring and bland conversations imaginable. I like to talk but Jay, arguably, likes to talk even more. So, there was a lot of content. The other thing was that we were filming in February. If it wasn't bright outside, the in-car footage wasn't usable. There was an amazingly organic moment when we were somewhere in the west of the country and Jay is trying to find a radio station. And he tunes into one just when they're in the middle of reading the death notices. And he's completely freaked out. I'm very excited because he's come upon a really brilliant snapshot of rural Ireland and the whole sequence was pretty funny. But, because it was night-time, we couldn't use it, unfortunately.

There's a very funny moment when Jay is recognised that just shows how humble a guy he really is.

When I first contacted him, I was expecting two things to possibly happen: a) to be ignored or b) to be subtly passed to his management and then I'd deal with them before being ignored. But from the first interaction, he was incredibly personable and supportive. Without him, this would never have gotten made. I owe him a lot. He's a different breed, really. Generous, giving, interested. And he genuinely thought nobody knew him when we were travelling around Ireland. We had dinner in a place in Galway one night and throughout the entire meal, there's an eerie silence in the room. He didn't pick up on it but I did. It was like everyone was on their best behaviour. We got up and went to settle the bill and everyone's eyes just followed him. Some guys were brave enough to give him 'the nod'.

Both of you become emotional at different points too. Was that something that surprised you going in?

Definitely. It's not a preachy film but because it's two idiots driving around different locations and acting the fool for large parts of it, the emotional moments are even greater currency because you're not expecting them. Like, there's an entire sequence in Westport which is just lovely to watch. It's filmed over an entire day and you can see how overwhelmed Jay is at night compared to first thing in the morning, because of what he's seen and done in between. By proxy, you can feel the weight of what your friend is experiencing and you get carried away by it too. There are a couple of moments in the film that show plenty of vulnerability but I think it's understandable given what's happening on screen.

Bringing a Hollywood star to your family home in Crumlin must've been slightly surreal, even if you were pals before?

I've found myself in the middle of quite a few bizarre moments in my life but introducing Jay to my parents was incredibly strange, mainly because they have no idea who he is or what he does, despite me explaining everything to him beforehand. At one point, when the cameras weren't rolling (unfortunately), my father turned to the poor lad and said, 'Now Jake (because that's what he called him), what is it you do again?' And Jay, because he's so lovely and kind, just kinda fudges the answer. 'Oh, I tend to write a bit and...' And my Dad just cuts him off, believing him to be a journalist. 'Well, you can write about all of the crazy people you've met in Ireland in your next article'. And at that point I have to interject and say, 'No, Dad - Jay writes movies'. But neither my Mum or Dad really knows that that means. In fact, they're still probably trying to figure out what I do for a living.

My missus was ideal for that entire scene because she was in her element. Born to perform, that one.

You shot the doc in 2016, I'm assuming you'd have loved to go back this year?

When we filmed, the standard of football wasn't the most thrilling but Celtic were still winning. So, from a filming perspective, it still works. And, ultimately, the conversations we had prior to shooting was that the actual game is a bit irrelevant because the story revolves around a first experience more than anything else. In theory, the Celtic v Man City game would've been amazing this season but then you get into logistical issues like getting Uefa approval, the difficulty/cost of using Champions League game footage, etc. So, in many ways, what we got was a perfect situation that we could control a bit more.

This season was magical and to intertwine so much with the 50th anniversary of 1967 was incredible. We live in an age when something that happened last week is so easily forgotten and that cheapens achievements like these. This team is a bit immortal now. It can obviously never come close to the European Cup side but to do what they've done is astounding and needs to be remembered and lauded for a very long time.

Have any other surprising Celtic fans popped out of the woodwork? Drew Carrey is apparently a Rangers fan.

I think some people have become Celtic supporters from watching this film, to be honest, particularly over here in North America. A lot of our audience is drawn to the emigrant/ancestry story and the Celtic stuff is a happy bonus. A lot of people have been learning about the club and its story for the first time. So, that's been lovely to see.

For screening times and locations, exclusive content and much more, check out the official website.

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