Tom Basden and Tim Key break hearts in The Ballad of Wallis Island, a movie with a jaded musician, an eccentric fan and gratuitous folk music.

By the time a film arrives on movie screens, its makers often strive to find ways to articulate how relevant it is, how it speaks to now.

Like many of us nowadays, I needed a reason to laugh. My mistake — encouraged by the offbeat bona fides of the British performers Tom Basden and Tim Key — was expecting “The Ballad of Wallis Island” to provide one.