“Runaground” is the real thing. Not almost the real thing, not promising-with-reservations, not wait-for-the-cast-album — the real, whole, thundering thing, and if you miss it at the Pemberton Theatre, you’re going to be explaining that to dinner companions for the next decade.

The show is adapted from Ernesto Vega’s 1977 cult novel about the Meridian Boys, a crew of teenagers who spend one overnight running from the Hunts Point waterfront to the bottom of Manhattan after their truce meeting with seven rival crews goes sideways. Director Valentina Cruz, working with book writer Javier Osei and a score by the composer duo Rima Adeyemi and Paul Salave’a, has turned that premise — which on paper sounds like a lot of running and no interiority — into something closer to a tragedy about what the city does to boys who love it when the city doesn’t love them back.

Here is what I need you to understand about Dario Reyes: he is twenty-six years old, this is his Broadway debut, and he plays the Meridian Boys’ captain, Tomás, with the kind of quiet authority that makes you forget to watch anyone else in a scene. It is not flashy. That is the point. In the second act, when the crew finally reaches the Hudson and Tomás realizes the cost of getting there, Reyes goes completely still — not theatrical still, actually still — and then he opens his mouth and sings “Meridian Blues,” and the orchestra falls out from under him and lets him carry it alone for sixteen bars. Sixteen bars. The entire Pemberton held its breath. I have been reviewing theater for fifteen years and I still wrote “oh” in my notebook.

The score is doing serious structural work throughout the night. Adeyemi and Salave’a write in a language that’s part 1970s soul, part hip-hop cadence, part classical through-line — and the book knows when to stop and let a number breathe. The opening of Act Two in particular: the Meridian Boys regroup on a rooftop set that collapses in real time as they sing, descending level by level through a lighting design by Charise Okonkwo that starts gold and bleeds to orange and finally to something close to ash. It’s one of the most visually precise sequences I’ve seen in a new musical in years. The staging doesn’t explain itself. It trusts you.

Pero — there is a but, mija. The first forty minutes are muddy. There are seven rival crews introduced in rapid succession, and while they’re differentiated by movement and costume, the book hasn’t given most of them enough lines to register as people rather than obstacles. The framing device — a fictional TV reporter narrating the night in hindsight — works beautifully in Act Two but feels obligatory in Act One, where we don’t yet know why we should care about the testimony. Cruz needs to take another pass at that opening and make a decision about who the reporter actually is to this story.

Jasmine Okafor, as the only woman in the cast with real stage time — a Meridian-adjacent runner named Celia who has her own reasons for wanting the truce to hold — gives a performance in an underwritten role that makes the thinness of the role obvious by contrast. She has one song, “Let Me Tell You About This City,” that stops the show cold. Then the script forgets her for forty minutes. That is a frustrating waste of a gift.

But listen. Here is what happens in that room by the time the finale lands: the audience doesn’t applaud at first. There’s a second — maybe two seconds — of silence. Then someone in the back starts clapping and the whole house comes up at once, including the man sitting next to me who had been skeptical enough at intermission to question whether he was going to stay.

He stayed.

You should too. Get to the Pemberton. Get there in the first month before the word fully spreads, because when it does, you are not getting a ticket. “Runaground” is not perfect — the first act has real work left to do — but the second act is worth every minute of the getting there, and Dario Reyes is about to become a name you already knew.

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