‘House full’: This musical keeps selling out. We go backstage to find out why

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Backstage at the Princess Theatre, a row of guitars lines the wall, each one tagged with the name of the song that will be played on it. There is a guitar for Sweet Caroline , another for Cracklin’ Rosie and one for Cherry, Cherry . The crew swaps them in and out through the night without missing a beat.

A Beautiful Noise: The Neil Diamond Musical tells the story of Neil Diamond’s life and career through 25 of his songs, including all the classics – performed by Broadway star Will Swenson – tracing his journey from struggling songwriter to international rock star.

From the seats of the historic venue, the audience watching the jukebox musical sees Swenson burst into song after song from Diamond’s career. For much of the night, the crowd isn’t just listening: many sway and dance in their seats, and sing along to the tunes they know by heart.

Behind the scenes, a live nine-piece band is turning that performance into a full-blown concert, the noise hitting the back of the room as hard as it leaves the stage.

That line of labelled guitars is the result of precision by a guitar technician, just one member of the huge army of unseen labour behind the show, which has been selling out during its Melbourne run (it finishes there on November 7 before its Sydney opening on November 14, before heading to Brisbane next year).

The Princess Theatre, which seats 1500 people, has welcomed more than 100,000 theatregoers since the show’s Australian premiere in August, and many performances have come close to selling out, with the “House Full” sign a regular sight out front.

That’s a change in a particularly tough season for musical theatre, with two blockbuster productions cancelled in June. Waitress scrapped its Sydney season because of weak ticket sales, a week after national dates for Beetlejuice were axed .

So why is this show the exception? We went behind the scenes to find out.

Sunk into a chair, a man dressed in muted attire leans forward with a heavy, bowed posture. There is no showmanship here, only an unvarnished sense of sadness and exhaustion. Before an audience anticipating spectacle, the man sits under a cool wash of lilac light – and begins to speak. It is one of the few moments all night when he is asked to do so.

The musical follows Diamond as a Brooklyn kid with a guitar who becomes one of the bestselling artists of all time. The older Diamond (played by Terence Crawford) watches on with a reflective eye, occasionally attempting to intervene in his own past.

It is framed by a present-day therapy session, in which the older Diamond reluctantly sits down with a therapist (Monica Sayers), who tries to encourage him to open up about the feelings behind his lyrics. A veteran of Australian stage and screen, Crawford plays Neil Diamond in the present. He is the musical’s fixed point: a man seated in a therapist’s office, watching his youth erupt behind him in song.

From the top of the show to the final bow, Crawford is absent for just two numbers. It is a strange brief.