Eurovision acts are known for being one-hit wonders. Can this year’s contestants, most returnees from the canceled 2020 event, break the stereotype?LONDON — When the Eurovision Song Contest was canceled last March because of the coronavirus pandemic, Vasil Garvanliev, North Macedonia’s entry, was distraught.“My whole life, I’d been working my butt off to get there and my journey didn’t even take off,” Garvanliev, 36, said in a telephone interview. “I was devastated.”For Garvanliev — and the event’s hundreds of millions of fans — Eurovision is far more than a glitzy, high-camp song contest. “It’s the Olympics of singing,” Garvanliev said.Last March he sat on his bed feeling depressed, he remembered, before picking up a keyboard to try to console himself. He started picking out a gentle melody on the instrument, then lyrics popped into his head. “Wait, it won’t be long,” he sung, “trust your heart and just stay strong.”“This song came out of me,” Garvanliev said, “and I thought, ‘Holy smokes, I have something beautiful here.’” Of course, “I didn’t know it’d end up being for this year’s Eurovision,” Garvanliev added. “I didn’t even know I’d be asked back.”For Eurovision 2021, the arena will be at 20 percent capacity, and no dancing will be allowed. Pool photo by Niels WenstedtBut in January, after an eight-month-long agonizing wait, Garvanliev was invited to perform at this year’s competition — one of 26 returning acts from Eurovision 2020. Scheduled for May 22 in Rotterdam, the Netherlands, 2021 is likely to be the strangest edition of the contest ever held — a high bar, given past winners have included Abba and Lordi, a Finnish heavy metal act whose members dress as monsters.The arena will be at 20 percent capacity, with just 3,500 people in the audience cheering the contestants on, while remaining seated to lessen the risk of coronavirus spreading. The event is officially part of a series of Dutch government trials to see how to run large events in a safe way. The contestants will all have made prerecorded versions of their songs in case they catch Covid-19 and are unable to perform.But perhaps the most unusual aspect is that all the returning contestants will be performing a different song from the one they had planned for the 2020 event. In a competition known for one-hit wonders, who disappear from view almost as soon as the contest ends, this year’s contestants have to prove they don’t fit that pattern.“This is our difficult second album,” Garvanliev said, referring to the phenomena of bands struggling to match their early success. He hoped his 2021 song “Here I Stand” wouldn’t fall into that trap.The entrant facing the biggest challenge in capturing last year’s magic is Dadi Freyr, Iceland’s act, with his band Gagnamagnid. Last year, Freyr was the favorite to win thanks to his song “Think About Things,” a catchy disco number about his newborn child.By the time Eurovision was canceled, the song’s video had been watched millions of times on YouTube. Soon, it was going viral on Twitter and TikTok too, after families started performing variations of the video’s dance routine while stuck at home in lockdown.“It changed my life, that song,” Freyr said in a video interview. Before the pandemic, Freyr generally only got booked for shows in Iceland, he said. Suddenly he was selling out tours across Europe.“I’ve probably had one of the best pandemics,” Freyr said.Freyr’s entry this year is another catchy disco track called “10 Years,” this time about his marriage (“How does it keep getting better?” he sings in the chorus). He felt he had to keep the track similar in style to “Think About Things,” since Icelanders had voted for a fun disco tune to represent them at the competition, he said. It still took 12 attempts to come up with a new song he liked, he added.The track’s so far not gone viral, but Freyr said that didn’t bother him. “I didn’t go to try and recreate the success, because I know it’s impossible to predict something like that,” he said. “Luck has to be part of it.”Four other Eurovision returnees said in interviews that they found the pandemic to be the biggest hurdle to writing a new hit. “For the first three or four months of the pandemic, I just didn’t do any writing at all,” said Jessica Alyssa Cerro, Australia’s entry, who performs as Montaigne.“I sort of got to November and was like, ‘Hmm, I should probably start working on that Eurovision song, huh?’” she added.Jeangu Macrooy, the Netherlands’ entry, said in a telephone interview that he similarly struggled. “I was getting no inspiration — I was just sitting inside,” he said.Then, in December when he was trying to write entries for the contest, a host of thoughts and feelings around George Floyd’s murder and the subsequent resurgence of the Black Lives Matter movement started bubbling up inside him.Soon he had conjured the lyrics to “Birth of a New Age,” an uplifting track about being “the rage that melts the chains.” Macrooy said he hoped it would speak to everyone standing up for their rights now, whether people of color, L.G.B.T.Q. people or the otherwise marginalized. The chorus of “You can’t break me” is sung in Sranan Tongo, the lingua franca of his native Suriname in South America.“It’s an ode to people claiming their space and saying, ‘I deserve respect and deserve to be accepted for who I am,’” Macrooy said. “I couldn’t have written it if I hadn’t lived through 2020,” he added.He’d recently been dreaming of people dancing to the track, he said, “so if that doesn’t happen at Eurovision, it’ll be awkward.” (The event’s current coronavirus safety rules prevent dancing.)For Montaigne, such dreams are now a thing of the past. She recently found out she would not be traveling to the Netherlands to compete, after Australian officials decided her attendance was too much of a coronavirus risk. Instead, Eurovision fans will have to watch the backup performance of “Technicolour,” which she recorded in March.Montaigne said she was fine with the decision, especially because she knew the pandemic was far from over in the Netherlands, with thousands of new cases of coronavirus currently being reported every day. “It would have been so bad if I was the person who brought coronavirus back to Australia, where we’re sitting in stadiums, having a good time dancing and touching each other,” she said.Even without attending, she still has a story to “tell my grandkids about,” she said. She’s the only Eurovision contestant ever to have missed the event twice because of a pandemic. More