Amidst all of the reboots and blockbuster franchises, "Shaun the Sheep Movie" truly stands out as one of the most delightful surprises of 2015.

A product of the U.K.'s beloved Aardman Animations ("Chicken Run," "Wallace and Gromit"), "Shaun the Sheep Movie" follows mischievous Shaun and his flock on an epic adventure into The Big City. What makes "Shaun" so special, however, is its lack of dialogue. With the exception of a few cleverly placed songs, there isn't any dialogue throughout the film's 82-minute runtime -- just various bleats, grunts and gibberish. But the emotion is extremely real, thanks, in part, to composer Ilan Eshkeri, a self-described "secret grown-up fan" of the "Shaun The Sheep" television series that inspired the film.

Since the characters don't talk in "Shaun The Sheep," the music has to speak for them. "The emotions are real and the emotions are big," Eshkeri told MTV News over the phone. "I know they're only little sheep, but the emotions that they're going through are real things and the feelings are big to the characters. Emotionally, you have to take them seriously, and that was the way we approached the film as well."

Shaun's heartfelt adventure begins when he decides he needs a day off from the daily grind at Mossy Bottom Farm. So he conspires with his barnyard buddies, including adorable, scene-stealing little lamb Timmy, to distract Shaun’s nemesis, Bitzer the dog, and lull their hapless farmer to sleep so they can relax on their day off. But Shaun’s plan quickly goes awry when the trailer they’ve locked the sleeping farmer in goes careening downhill and into The Big City -- with Bitzer in tow.

To score this charming story, Eshkeri relied on an eclectic mix of genres, from classical, to barbershop, to heavy metal. For example, while life on the farm is bubbly and bright, if not slightly mundane for Shaun's taste, The Big City is more sinister, especially with an overzealous animal control officer named Trumper running the streets. His scenes are accompanied by a sinister metal riff.

But nothing encapsulates the emotions of the film quite like "Feels Like Summer." Not only does the sunny pop song open the film -- as Shaun recalls halcyon days with the flock and their Farmer -- but it serves as the movie's recurring, heartfelt theme.

Eshkeri wrote the poppy song with Ash's Tim Wheeler and Kaiser Chiefs' Nick Hodgson, with Wheeler handling singing duties. Their only note from directors Mark Burton and Richard Starzak was to make the track reminiscent of '90s Brit Rock. "We needed something that instantly like sounded as though you'd heard it before," Hodgson told MTV News. "Like a classic, lost record."

"They wanted a British thing," Eshkeri added. "There was this idea that this farmer got his farm in the '90s and maybe he listened to a lot of British rock bands of that era."

Inspired by British bands like Oasis and Teenage Fan Club, the trio set off to write a song with "that sort of jangly, sing-along, kind of indie feel-good" vibe. Eshkeri was inspired by his own halcyon days, sitting in the park with his friends.

"I can remember being a teenager and listening to Oasis and Blur and in fact, to Ash, Tim's band, in the park in my early 20s, and just hanging out and having those great summers that you have at that age with your friends," Eshkeri added. "Where it seems like this sort of carefree life is going to go on forever. And there was something like that I think we tried to capture."

When it came time to record the demo in Hodgson's London studio, Wheeler temporarily took over the lead vocals, a decision that ultimately stuck.

"At first I thought I was just singing the demo for fun," Wheeler told MTV News. "We hadn't really talked about me being the singer on it, as we were working on the lyrics with the guys. I sang on it and it kind of stuck, so it was very relaxed and a fun thing.... I was so hungover. I was really quite broken actually."

In many ways, "Feels Like Summer" is the soul of the film. When their Farmer gets a terrible bout of amnesia, it's the song that ultimately reunites them. As if setting the mood for the entire film wasn't pressure enough, Eshkeri had to re-record the song using "baas" and bleats for a scene in which the sheep, all alone in The Big City, form a baa-bershop quartet and sing little Timmy to sleep.

Needless to say, Eshkeri recorded the baa-rilliant track (several times) with "tears of laughter" streaming down his face.

"It's the thing that jogs the farmer's memory and makes him remember his family," Eshkeri said. "So the song is very literally the soul of the film, and it's also so intertwined into the score. When I was writing the score, there's 20 or 30 references to the chorus of the song in addition to the other places where the song is played, in addition to the baa-bershop quartet where the sheep sing it halfway through, which I had to do."

"I'm always mortified because I'm Sheep #2 [in that version], and I'm not used to being in the limelight," he added. "I'm like, 'Oh, my voice sounds awful.' It's so weird seeing my voice come out of an animated sheep."

The song, in all of its iterations, truly resonated with audiences around the world. You don't need to bleat to understand the meaning behind "Feels Like Summer." It's that feeling of pure joy, of something so innocent and bright.

"We've actually played it at an Ash show in China," Wheeler said. "It's absolutely massive in China. We were playing at festivals, so they asked up to play it. I think it had slightly louder guitars on it than the recorded version. I remember some people were very keen to dance on stage in 'Shaun the Sheep' costumes, but we weren't quite sure about that... It was quite cool to see people dance to it. It just makes everyone happy."

We'll bleat to that.