Billy Bob Thornton was reduced to tears when he watched his new movie 'Standing on the Shoulders of Kitties', writer-and-star Mike Smith has revealed.

The comedy film - which is based on the Canadian TV series 'Trailer Park Boys' - sees Mike's character Bubbles form a country band and then get offered a European tour supporting Thornton's rock group the Boxmasters.

Mike and Billy have been friends for around 10 years and the comic actor wrote the movie with him in mind.

When the pair watched 'Standing on the Shoulders of Kitties' together at a premiere held at Abbey Road Studios - the iconic London recording studio where The Beatles made their albums and which serves as the location for the film's finale - Mike was astonished to see the 'Landman' star crying over one particularly poignant scene, and it was a moment that filled Mike with immense pride and happiness.

Speaking to BANG Showbiz, Mike recalled: "We went through the movie. We made it, we cut it, we worked on it and then we had the first premiere at Studio Two at Abbey Road. I sat at the very back of the room next to Billy Bob. We watched the movie, and Billy hadn't seen the finished cut at this point, so it's the first time he's watching it. And there's a scene at the end, where Bubbles is going to sing this song that he's been working on through the movie and Billy gives me a pep talk and some advice in Abbey Road.

"Billy says, 'Are you sure this is the song you want to sing?' He coaches him and then there's this moment where Bubbles basically sums up what his whole life is about, cats are the whole reason he's the person he is and he's going to sing this song.

"So we're sitting there and watching the movie and I'm trying to watch Billy to see his reaction, because it's our big scene together, and I'm looking at him and I'm like, 'F***, I think he's got a tear in his eye.' So I just look at him and he's crying. He looks at me and goes, 'This is a really f****** powerful scene dude.' And then I started crying and go, 'It is, isn't it.' So me and Billy are sitting their crying whilst watching the movie. That to me made the whole thing worth it in that moment.

"After that, a few hours later, we're drinking at the bar, Billy says, 'Dude, just so you're aware I don't cry at movies and s***. That was really f****** cool.' That was the greatest moment for me through the whole process. From the time I talked about making the movie and writing the songs it was, like, six or seven years ago. So to go through all of that and then finally make it and then finally watch it at Abbey Road and make my hero cry, was pretty cool."

Mike admits he was nervous to even ask Billy, 69, to star in the movie, because he knew he couldn't pay him anywhere near the salary he commands for his roles.

However, the 'Goliath' actor didn't hesitate to agree to appear after he read the script and loved it.

Mike said: "I wrote it with Billy in mind. Then I was drinking one night and got up the courage to call him and pitch it to him.

"When I pitched it to him, I said, 'Look, I know what you are worth. I know roughly, probably, what you get paid. I know we can't come anywhere near that. So, I don't want to insult you, but I wrote this thing, it's a music based thing and I think it'll be fun. Would you look at it?

"He was like, 'F****** right. Send it right now. I'd love to read it.' Billy's, like, the nicest dude. I was all shy and nervous. I'm asking an Academy Award winning actor, 'Hey, can you do my s*** movie for no money?'

"So I sent it to him. He was on tour, and I thought, 'Well, if he reads it in the next month, it'll be great.' He calls me back, like, two days later, he says, 'Dude, the script is awesome. I want to do this. Let's do this f****** movie.' And I was like, 'OK, Billy Bob Thornton.' So that it was pretty mind blowing."

'Standing on the Shoulders of Kitties' is directed by Charlie Lightening, who made the Liam Gallagher documentary film 'AS IT WAS' and has worked as Sir Paul McCartney's documentarian for the last 16 years.

Charlie admits he had some nerves about directing Billy in the film but the Oscar winner just amazing to work with.

Charlie said: "I was going into it, definitely nervous. I've made massive music videos, been on big sets but it was the fact I was going over into their world.

"There was a great moment while we were shooting in Europe. There was this one scene, and it just wasn't working, and we were pushed for time.

"It was the coolest moment because Billy could have just gone, 'Listen, we're doing it like this.' But he just goes, 'Hey bud, can we go and have a cigarette.' So we go outside and he has a cigarette and he goes, 'I have a couple of suggestions and ideas, if that's OK?' I was like, 'Are you f****** kidding me?'

"It was great, because there were no egos, we were all in it together."

'Standing on the Shoulders of Kitties' also stars 'Trailer Park Boys' regulars Robb Wells, JP Tremblay and Pat Roach, as well as Martin Freeman, Robert Sheehan and Rolling Stones legend Ronnie Wood.

The movie is out now and can be watched in Vue cinemas from 10th January.