Having come into this year’s Sundance a bit saddened at no John Carney (Once, Sing Street) film on the slate, The Ballad of Wallis Island arrived and made me feel all warm inside in much the same way. A story of love, loneliness, connection, and of course, music, this cheeky British comedy is the brainchild of co-writers and stars Tim Key and Tom Basden, building from their 2007 short. It’s for sure a breakout performance by Key, whose lovably open-hearted fanboy Charles is the note that brings this melody together.

It would be so easy to dislike Charles, and admittedly, I thought I would in the beginning, too. He’s the kind of guy with no filter and little self-awareness. He says what’s on his mind and what typically comes out of his mouth are an array of Dad jokes and praise for his all-time favorite band, the Swell Season-esque folk duo McGwyer-Mortimer. Charles is so lovable we don’t even mind that he’s won the lotto….twice, after spending it all the first time on an international journey (“Kathmandu? More like Kathman-did”) before retiring to the fictional island hideaway. With more money than he can possibly spend, Charles does the one thing he’s always wanted, which is hire the band for a private gig on the island.

The problem is that McGwyer-Mortimer broke up years earlier, as musical and romantic partners.  It’s Herb McGwyer (Basden) who shows up on Wallis Island first, surly and in a creative funk. Also very wet…there’s no dock at this harbor, either.  Charles hasn’t been completely upfront with him about everything, either. While Herb is doing this gig to pay for the next album, a misguided mainstream effort, he’s curious as to why Charles would pay him an exorbitant amount to do a solo show for “less than 100” people. He’s also shocked to find out that he’ll be staying in Charles’ home, with a constantly-running tap (“it works too well”), zero amenities, and no privacy.

Producer and star Carey Mulligan enters the picture as Nell Mortimer, who has given up her music career to make chutney with her bird-watching husband, Michael (Akemnji Ndifornyen), who seems like a fine if slightly dorky chap. Charles had conveniently forgotten to mention that part of the arrangement (“she accepted late!”), and Herb is not ready for the rush of emotions that come with her arrival. At first, things are quite icy between them. There are still a lot of hurt feelings, professional and personal, but they still click musically. You can feel it when they start playing together, it’s like you’re watching something magical being brought to life right in front of you.