Image copyright Eurovision Image caption The Eurovision 2019 entries for (from left to right) Greece, Switzerland, Belarus, Iceland and France

"It's every artist's dream to perform on this stage," explains 16-year-old singer Zena.

As this year's youngest Eurovision Song Contest contestant she can't hide her excitement at taking part in the "most popular contest in the world".

She's representing Belarus at the competition - held in Tel Aviv, Israel, this year - and is one of the many acts helping transform Eurovision's image, which is sometimes seen as a bit of a joke in the UK.

Other countries have spent years developing a formula hoping to win - and host it the following year - by sending some of their most popular and critically acclaimed acts.

The show is the world's biggest live music event and is hugely popular with younger viewers.

Eurovision says in 42 markets, the contest was four times more popular with 15-24-year-olds than the average show.

You can watch Eurovision: What's the Fuss? on iPlayer here if you're in the UK, or on YouTube if you're not.

Most acts taking part in this year's contest are under the age of 30, but Switzerland's Luca Hanni jokes he feels old at 24.

"It's amazing to see all young people competing," he says.

Eurovision is a week-long event with a red carpet, two semi-finals, a grand final and this year Madonna will be be performing.

But the build-up goes on for months and people like 18-year-old Gemma Lee see it as a "legitimate place to find new music".

Gemma and her mates started a Eurovision society at Bristol University to discuss what her friend Luke Hardwick calls "the World Cup of music".

"This year there's a real mix of genres," Gemma says. "It's a refreshing thing that anyone can watch Eurovision and there's going to be something for them."

On a Saturday night in April, 5,000 fans packed into an arena in Amsterdam for the first big Eurovision party of the season.

Most of this year's 41 acts performed to a crowd waving flags and glow sticks, headlined by the Dutch entry Duncan Laurence - one of this year's favourites.

Image copyright Paul Bellaart Image caption Duncan Laurence is a fairly unknown artist in the Netherlands but is currently one of the favourites to win with his song Arcade

"I think tonight comes as close as it can to Tel Aviv," the 25-year-old tells Radio 1 Newsbeat.

"Eurovision is a big stage for me, especially as a new artist," he says. "I see it as a chance to show myself and let people hear my music."

Backstage, contestants are meeting each other for the first time, eyeing up the competition and making friends.

Just before speaking to Newsbeat, Spain's Miki Nunez, 23, is overheard championing Belarus' Zena.

He congratulates her, gives her a hug and tells us that young people "have a lot of things to say about society" and the contest is a "good opportunity for us to express ourselves".

Image copyright José Irún Image caption Spain's representative Miki is part of the so-called "big five" who don't need to qualify for the final along with France, Germany, Italy and the UK

A week later, 18 of the acts arrive in the UK for the London Eurovision Party at the city's Cafe De Paris.

The UK's entry Michael Rice is chatting about his Amsterdam experience.

"My mates think it's crazy that I'm going to all these different countries," he says. "They're just seeing bits on Instagram and all the fans."

He thinks it's a good thing the UK doesn't send joke acts and "it's about time" it took the contest seriously.

Standing next to Michael is one of this year's most talked about participants - France's 19-year-old entry Bilal Hassaini.

He describes himself as a gay, queer man who performs in drag - and says he gets "a lot of hate and backlash" because of it.

"I've been struggling with my identity for a long time and I've finally found the strength to ignore others."

Image copyright Dorothée Murail Image caption Bilal has been a huge Eurovision fan for years and says he wants to help young people in countries who don't have someone like him on TV

Embracing diversity is a sentiment that resonates with LGBT fans, who make up such a large part of the Eurovision community.

Notable moments in the contest's 64-year-history include drag queen Conchita's win in 2014 and Dana International, a transgender singer, winning for Israel in 1998 with her song Diva.

Last year, Ireland's performance included two men dancing as a couple, which led to censorship in China.

Controversy this year could come from Iceland's entry Hatari, with their BDSM-inspired outfits of leather, spikes and PVC - and their claim that "every act needs a gimp".

Media playback is unsupported on your device Media caption Hatari's song is called Hate Will Prevail

Eurovision rules say acts need to be strictly non-political during their performances, but Tel Aviv is proving a controversial host because of the Israeli-Palestinian conflict.

Some stars have called for the contest to be moved from Israel, while others want countries and contestants to pull out completely.

Hatari, who say they entered the competition because they want to shed light on political aspects of Israel, admit their stance "is a contradictory one".

"A contest like Eurovision was founded in the spirit of peace and unity," singer Matthias Haraldsson tells Newsbeat.

"We find it absurd to host it in a country marred by conflict and disunity. Allowing that narrative to go on unchallenged would be a shame."

The band insist they'll stick to the strict Eurovision rules by not making any political statement during their performance.

Kobi Marimi - the Israeli entrant - believes the contest "celebrates music and love" and Greece's Katerine Duska says she "performs for people, not governments".

Image copyright Ronen Akerman Image caption Israel's entrant Kobi Marimi will be performing a song called Home

One country which isn't sending an act to Tel Aviv is Ukraine, after its entry Maruv pulled out of the contest.

She was challenged on Ukrainian TV about her views on Crimea - a disputed area of Ukraine that Russia seized in March 2014.

Ukraine's state broadcaster then asked her to cancel gigs in Russia as one of the conditions of her being its Eurovision entry.

After a dispute, she quit the contest.

Image copyright Getty Images Image caption Maruv believes her track Siren Song would have won the contest - or "at least be top five" - as it was "100% one of the best songs"

Speaking to Newsbeat she explains: "It was my dream to represent my country at the competition but I'm in a song contest, not a political arena.

"I was sad and upset to pull out as I wanted to have the experience but I won't compete again."

Referring to her decision, co-host of the BBC's Eurovision Calling podcast Jayde Adams said it shows "Eurovision is not just about a singing competition - it's more than that - it's about the world and how people fit in it."

Last year around 186m tuned in to watch Israel's Netta win with Toy - a song about female empowerment.

Image copyright Getty Images Image caption Since winning the contest in 2018 Netta says she's been able to go from a struggling musician to being someone who can help others "accept their differences"

Of all the countries in Eurovision, Sweden takes its selection the most seriously - and is rewarded with consistent top ten finishes.

Arguably, Loreen's win for Sweden in 2012 was a turning point in the transformation of Eurovision.

Her anthem Euphoria won by a mile, going to number one in 17 countries and reaching number three in the UK charts.

This year John Lundvik is representing Sweden and describes Eurovision as "the holy grail" of music.

Image copyright Getty Images Image caption John Lundvik won Sweden's Melodifestivalen - the national competition to select its Eurovision entry - watched by a huge percentage of its population

He admits the contest used to be "corny" but says it's evolved into a "super-fashion-hit-song, super-artist-thing that's now cool to be a part of".

Also an early favourite with his song Soldi, Italy's Mahmood tells Newsbeat that less is more when it comes to the performance.

"If you do something minimal and cool and unique then I think it's a beautiful chance to show how a country can do something modern and interesting."

Image copyright Attilio Cusani Image caption Mahmood says Eurovision is "a great opportunity for a country to promote its art" because it's such a huge show

UK entry Michael Rice agrees with John (who also co-wrote the UK's entry) and Mahmood, saying many people see Eurovision as a "gimmick" but in reality "you're never going to get a platform like this again".

In recent years, the UK has consistently appeared in the bottom half of the Eurovision leaderboard but that's not the focus for Michael.

"It's so surreal and a huge honour to be representing my country. It's a great achievement for me as I'm only 21 years old," he explains.

"It's going to be something I can look back on and think 'I did Eurovision'.

"I just want to make everyone proud."

Image copyright BBC/Joe Giacomet Image caption Michael won the BBC's All Together Now show in 2018 - putting most of his £50,000 winnings towards a crepe shop for his mum in Hartlepool

The Eurovision final takes place on Saturday, May 18 at 20:00 BST and is on BBC One, BBC Radio 2 and BBC iPlayer.

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