Alchemy like that they don’t teach at Hogwarts.

A related kind of alchemy is at work in “Harry Potter: The Exhibition,’’ which opens tomorrow at the Museum of Science and runs through Feb. 21. It transmutes marketing into entertainment. The show is a giant ad - a slick, skillful, and enjoyable ad - for the “Potter’’ movies. The books? Forget about the books. The books don’t generate income for the corporate parent of Warner Bros. Consumer Products, the show’s promoter.

More than 200 items from the movies are on display. Viewers get to see Harry’s glasses; his Nimbus 2000 broomstick; the Sorcerer’s Stone; framed pages of The Daily Prophet (is there an online edi tion?); a mock-up of the Hogwarts Express locomotive; a bottle of pumpkin juice (very seasonal); the Triwizard Cup, which looks much more impressive than the NFL’s Lombardi Trophy; the Golden Snitch; and many wands (Harry’s, Dumbledore’s, Voldemort’s, you name it).

In a league of its own is professor Umbridge’s office. The decor - can pink be Brutalist? - is like a fever dream shared by Margaret Thatcher and Reese Witherspoon in “Legally Blonde.’’ Harry, Ron, and Hermione are all over the show. But lesser (and darker) lights like the Malfoys, the Dementors, professor Lockhart, and Umbridge are here, too.

The props and costumes are displayed in themed environments. Galleries resemble part of the Gryffindor Common Room, Hagrid’s Hut (you can sit in his armchair), dorm rooms, the Great Hall, and so on. A quidditch display lets you toss a quaffle, albeit from a standing, earthbound position. Monitors ceaselessly show clips from the movies. John Williams’s music fills (and fills and fills) the air. It’s the sort of sensory overload that’s hell for anyone over 40 - and heaven for anyone under 14. An attendant mentioned overhearing a young boy declare, “This has been the best day of my life!’’

The attendants are a sign of the care, and calculation, with which the show has been put together. Part of the appeal of the series is its being so drenched in Britishness. With that in mind, the attendants have either been brought in from Britain or are actors. Hearing your questions replied to in a British accent is a nice authenticating touch.

Young men and women in their 20s, the attendants seem genuinely friendly and helpful - cheerful, too - though let’s see how long the cheerfulness lasts. It’s even money that by Thanksgiving they’ll be plotting the death by strangulation of John Williams. How would you want to have to listen to that music every day over and over again for four months in a confined space? Even Azkaban doesn’t hold such terrors.

The attendants are there to answer questions - and also for crowd control. The show’s pleasures can be highly pleasurable enjoyed at one’s leisure and with a little elbow room. But expect elbow room to be at a premium.

It’s great fun, for example, to wear the Sorting Hat and get assigned to a house. Or, rather, it’s a lot of fun for those who manage to do so. The display is limited to just two visitors per five minutes, or one per group. You don’t want to be the parent who has to tell his or her children they have to go hatless.

Crowd considerations, presumably, are also why there are relatively few interactive features and the explanations on the audio guide so brief. Interesting as it is to hear the tech people who created the props talk about their designs, it would be that much more interesting to hear these real-life wizards at greater length. The little we learn about their techniques and processes is as close as the show comes to science. At least the 2005 “Science of Star Wars,’’ the touring blockbuster show at the museum that most resembles the “Potter’’ show, had some real, well, you know, science in it. Craft, and not much of that, is about as good as “Potter’’ gets from any sort of educational perspective.

Let’s hear it for the costumes, then. Their appeal will surely be lost on most visitors, but they may be the single best thing in the show. Their craftsmanship is superb. The quidditch uniforms, for example, are quite something. In the movie, a viewer is so caught up in the action they practically go unnoticed. Here you realize they’re like something you might see on an Art Deco football field.

There’s a flurry of clothes in local museums right now - “Rare Bird of Fashion,’’ the Iris Apfel exhibition at the Peabody Essex, “Mary McFadden: Goddesses,’’ at MassArt. The “Potter’’ robes and gowns are no less worthy of attention. The designs are often ingenious. And that’s not even factoring in the associative frisson involved in seeing, say, Severus Snape’s robes up close. Who knew that purple could ever look so grim?

Of course the color that matters here isn’t purple but green. The exhibition concludes with a large commercial space. Postcards go for 69 cents each - four for $2. The only thing that sets the store apart from the show is its bright lighting. The galleries are a very different matter. Their windowless, black-box environment is like the interior of a casino. “Harry Potter: The Exhibition’’ would fit right in as an attraction at Foxwoods or Mohegan Sun. It would certainly track better with a casino’s mission statement.

Mark Feeney can be reached at mfeeney@globe.com.