Unfortunately, almost the last thing that Million Dollar Quartet feels like is an impromptu jam session. What it is, instead, is a musical drama—albeit one lacking in suspense, since we know before it starts how it will come out—about Sam Phillips, presented here as the founding pioneer of rock & roll, and how the 'boys' whom he nurtured to fame one by one abandon him. Interspersed throughout this drama are the songs of the jam session, often played in snippets so that the story can play out literally between verses. (For example, 'Great Balls of Fire,' the climax of the session in this musical, is interrupted twice by Phillips's soliloquizing.) Because the narrative is constructed so snugly around and within the songs, and because the performances are glitzily polished (as one would indeed expect at a Broadway musical charging $125+ for tickets), spontaneity is pretty much vanquished from the proceedings. And of course spontaneity would seem to be the precise feeling that the creators of this show ought to be going for if they want to re-create the unplanned brilliance of that famous evening.