NEW YORK — “Interveno ticketmasterus!”

I’m wondering if the wizarding world could come up with a charm that might give desperate Muggles a leg up on performance availability. Because an incantation may be the only way to scare up tickets to “Harry Potter and the Cursed Child,” now that it has officially opened on Broadway and Potterholics are going to be hitting the ticket-buying website refresh button so often they’ll be in danger of breaking keyboards and fingers.

This elaborate two-part, 5½ -hour stage sequel to J.K Rowling’s canonical series is like a witchy worship service for the countless consumers of every magical segue and subplot of the seven books and eight Harry Potter movies from which it draws inspiration. During the full day of performances I attended in the Lyric Theatre — refurbished as part of the production’s reported $68 million, pre-opening budget — roars and applause broke out for the entrances not of star actors, but of familiar supporting characters like Albus Dumbledore, Severus Snape and Dolores Umbridge. If that is any indication of a devotional intensity waiting to be tapped, this deft homage will be inducing swoons in Times Square for years to come.

In the face of such overarching eagerness, do a humble reviewer’s words have even a glancing significance for the box office? Probably not, and especially because reasons abound for the books’ fans to be justified in their fervid anticipation. Director John Tiffany and his longtime maestro of movement, Steven Hoggett, who collaborated on “Black Watch” and “Once,” among other shows, have created a dynamic pair of evenings replete with ahhhh-inspiring tricks and illusions overseen by the ingenious Jamie Harrison. (Christine Jones’s swirling breakapart set pieces and Neil Austin’s lighting effects are marvels, too.) Some of these elements inspire wonderment even in Potter newcomers, such as the friend I brought, who was prepared to be swept away but found the experience sometimes difficult to engage with. (More on his reactions in a minute.)

The plot is — no pun intended — another story. Dreamed up by Rowling, Tiffany and Jack Thorne, a dramatist best known for the chilling “Let the Right One In,” the rambling narrative is so filled with barely elucidated references to creatures and past events from the novels that you really do need, in a sense, to have been there. (Make sure you know what’s meant by a “Tri-Wizard Tournament,” for example.) I was supposed to be accompanied by my Potter-trained daughter, Lizzie, who is now in her 20s and had each new book couriered to her at summer camp, but she was working that day, and so I invited my friend Lee, a retired professor of speech and drama, to come in her stead.

And for the first 90 minutes of Part 1 — which sets in motion the tale of the grown-up Harry’s teenage son, Albus Severus Potter, who is alienated from his father and having trouble at Hogwarts, the school for wizards and witches — Lee might as well have been stunned by a wizard who’d pointed a wand at him and shouted, “Mystify!”

“I don’t have a clue what’s going on. Not a clue,” Lee said at the day’s first intermission. The accompanying expletives have been omitted.

Compared to Lee, who has a real doctorate, my knowledge of all the backstories, having been gleaned by reading behind Lizzie and seeing the movies with her, qualified me for a PhD in the dark arts. As you might imagine, the volume of detail about a fantasy world disgorged over two shows containing some redundant tricks could be particularly wearying to anyone not previously acquainted with Cedric Diggory, or Hagrid the half-giant, or the Ministry of Magic. And even I, at the umpteenth voyage back in time, courtesy of a rotating orb called the Time Turner, was ready to pack it in by the middle of Part 2.

The ushers hand you a button at the end of each part asking you keep the shows’ secrets, and so I will dispense with describing some of the wonder-filled illusions. The leading actors, all of whom traveled to New York from London, where they originated the roles, are jolly good, but presumably are fairly easily replaced: Noma Dumezweni is particularly apt as Harry’s longtime friend and now co-worker, Hermione Granger, and Alex Price adeptly masters the tricky assignment of turning Harry’s old nemesis Draco Malfoy into a character of more complex motivation.

Many of you will get the opportunity to discover all this on your own, if you take to heart a bit of critical advice. Not the hackneyed command that you “Go and Enjoy!” But in seeking out your reconnection with The Boy Who Lived, the harder words to hear, occasioned by overwhelming demand: “Be patient!”

Harry Potter and the Cursed Child (Parts 1 and 2), by Jack Thorne, based on a story by Thorne, J.K. Rowling and John Tiffany. Directed by Tiffany. Illusions, Jamie Harrison; sets, Christine Jones; lighting, Neil Austin; sound, Gareth Fry; costumes, Katrina Lindsay; movement, Steven Hoggett; music and arrangements, Imogen Heap. Part 1: 2 hours and 40 minutes. Part 2: 2 hours and 35 minutes. At the Lyric Theatre, 214 W. 43rd St., New York.