The popular folk-rock band helped raise the curtain on the new musical, for which they provided music and lyrics

But “Swept Away” has washed up on Broadway via a much-trafficked route in contemporary theater: Load up on existing tracks from a popular recording artist — the Avett Brothers, in this case — assemble a crew with bona fides and set sail.

There’s so much to recommend this sterling Broadway staging that it seems unkind, or even unfair, to call the musical a misfire.