Eurovision: How Ariana Grande's songwriter got involved in Will Ferrell's new movie

Savan Kotecha regularly works with some of the biggest acts in the world including Ariana Grande, Demi Lovato and Ellie Goulding.

Now, he's got a fictional Icelandic duo called Fire Saga at the top of his CV.

The hopeful-but-hopeless singers, played by Will Ferrell and Rachel McAdams, are the focus of Netflix's new comedy Eurovision, which celebrates the world's largest live music event.

As a hugely successful pop songwriter and producer, Kotecha was brought in to oversee every aspect of the film's music.

"It was a blast," he tells Newsbeat. "It's probably the most fun I've had on a project in a long time."

The film plays out like the real life contest, with every country having their own ready-made song.

Kotecha's role involved composing and building teams of experts to write them, which included bringing in songwriters who'd worked on real-life Eurovision entries.

He says if you take some of the most memorable songs in the contest's history, then "break down the spectacle and the big productions" you find "some really good melodies.

"We wanted to make sure the melody was at the core and to make songs feel like they'd actually have a shot at actually winning."

What you get are comedy entries like Iceland's Double Trouble and Russia's Lion Of Love - but with the production values of real-life hits and the staging of Eurovision greats.

"The melody of the chorus in Double Trouble was actually something I had in my phone that I was saving for a pop star."

Even though the artists he worked with for the film are fictional, Kotecha approached the production and songwriting process in the same way he'd work with singers like Ellie Goulding or Ariana Grande.

He wanted to "understand their personality and the countries they were representing".

Savan Kotecha's songwriting CV includes:

Kotecha, who's American, says he "reluctantly fell in love with Eurovision" because - like Will Ferrell - he has a Swedish wife.

Sweden is one of the contest's most successful countries and Loreen's 2012 winner Euphoria is his "ultimate Eurovision entry".

"The first year I lived in Stockholm, the whole place shut down for Eurovision parties. It took me a few years to get used to it.

"But then you realise the contest is about unity, sharing cultures and - of course - the kooky performances. It's a beautiful thing."

Among the movie's fictional artists (like Dan Stevens' Russian lothario Alexander Lemtov) are some real life bands, including London-based Anteros.

In the movie, they represent Finland (as made up band The Wonderfour) but get to perform one of their own songs, Full Moon.

Confused?

"None of us have ever been to Finland," says Anteros' lead singer Laura Hayden (AKA Lala), who thought the request to be in the film "was a joke".

They'd been hand-picked by Will Ferrell and director David Dobkin, who liked their style and sound, and wanted to transfer their song to the stage.

"It's really surreal watching your baby being taken to a big stage and then being Eurovisioned."

"The whole thing was weird because we were performing our own song, there's a crowd of people cheering and shouting, waving flags… but obviously none of them knew the track."

Laura also found herself in a make-up chair next to her idol Rachel McAdams and wondered "is this real life?".

In the film, Rachel McAdams performs alongside Will Ferrell, but her main singing voice is actually that of Swedish star Molly Sanden.

She tells Newsbeat the movie gets the right balance between "sarcasm and irony" and "showing off the good parts about the competition".

Molly was approached about the role by one of her producer friends when she was on holiday in Los Angeles.

She connected with the character of Sigrit because it reminded her of a childhood ambition to compete in Eurovision herself, as she tried hitting high notes in her basement.

It became a reality when Sanden represented her country in the Junior Eurovision Song Contest in 2006, placing third.

She then entered Sweden's Eurovision selection contest, Melodifestivalen, three times but never won.

"I felt like a failure the last time I tried to compete for Sweden because the plan was for me to win. It now feels so good to come back from this angle."

"It feels like I'm coming back to Eurovision… but this time I'm winning."

There are no spoilers, but for Eurovision lovers, the film has lots of little nods to previous contests - including some high profile cameos.

And even though he was a "reluctant fan" in the first place, Savan Kotecha says he's up for getting involved in the real thing if a country approached him to help write a potential winner.

"Totally," he says. "I think it would be really fun."

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