Thursday night in American multiplexes, the conch shell sounded. Disney’s live-action Moana opened its preview run with $4.5 million across Thursday showtimes — a number that, in Hollywood’s particular arithmetic, tells studios almost everything they need to know before the weekend count begins.

The preview haul puts the film in workable territory by recent standards. The closest comp is Ghostbusters: Frozen Empire, which took $4.7 million in previews last year before landing a $45 million opening weekend. A notch above that sits Pixar’s Lightyear, which posted $5.2 million in previews on its way to a $50.6 million three-day debut. Neither film is an identical match — genre, IP age, and audience overlap all factor in — but both give industry trackers a sensible band to work within.

For Disney, the live-action remake pipeline has produced results ranging from runaway hits to awkward stumbles, and the studio will be watching the weekend multiplier closely. The original 2016 animated Moana opened to $81 million domestically, a figure that functions less as a direct benchmark than as a ceiling the live-action version almost certainly will not approach — but which gives the franchise brand real weight at the ticket window.

Audience composition and Saturday-day holds will sharpen the picture considerably. A family-skewing title like Moana typically builds through Saturday before softening Sunday, and a hold above 90 percent day-over-day would push final estimates toward the higher end of current tracking. Full three-day numbers are expected Sunday afternoon.