“Once, the Musical” is a simple plot set in between intricate songs: Over five days and 16 musical numbers, Guy (Tom Frank) and Girl (Aurora Florence) record a demo album and, though still reeling from past relationships, begin to fall in love.

The 3-D Theatricals production running through this weekend at the Cerritos Center for the Performing Arts uses that theater’s pneumatic system to stage the production in the round, allowing Edna Walsh’s adaptation of the 2007 John Carney film to unfold with the intimacy that “Once” fans know well.

As directed by Kari Hayter, the musical’s set pieces are minimal. The supporting cast also serves as the orchestral accompaniment. Original music and lyrics by the film’s stars, Glen Hansard and Markéta Irglová, are very much the heart. The songs are the connecting point between not only the two leads, but also the characters and the audience. (“Falling Slowly,” the Oscar winner for original song, is just one example of the music’s power.)

The musicians are strong performers with a commanding presence, and the numbers in which the cast moves in complete sync while song bursts from the stage are arrestingly memorable.

“Once, the Musical” is buoyed by its musicianship and in-the-round staging at Cerritos Center for the Performing Arts.

(Caught in the Moment Photography)

In between the songs, however, the connective contextual tissue is not nearly as good. The story requires much suspension of disbelief: These characters are meant to be in love after knowing each other for only a few days. We’ve seen this done before, for story’s sake, but it requires persuasiveness from, and chemistry between, the actors for the full weight of emotions to land cleanly and effectively. Frank and Florence shine during the songs, but they don’t present a convincing love connection. They proclaim their love for each other, but it comes across as just that: a proclamation, not the real thing.

Their strength lies in their musicianship. So if the songs are what really matter to you in musicals, “Once” succeeds.

‘Once, the Musical’

Where: Cerritos Center for the Performing Arts, 18000 Park Plaza Drive, Cerritos

When: 8 p.m. Friday, 2 and 8 p.m. Saturday, 2 p.m. Sunday. Ends Sunday

Tickets: $25-$90

Info: (562) 916-8500

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