With the new two-part play Harry Potter And The Cursed Child getting ready to make its West End gala bow in London tomorrow night, producer Colin Callender is in jubilant form. He has every reason to be — the play is setting sales records and just announced an extension of its run through December 10 2017. From the very first previews of Part One and Part Two, the audience response to the play, which Callender produces alongside Sonia Friedman, has been ecstatic, and critics have raved about director John Tiffany’s production.

The all-new story picks up the action 19 years after the great battle at the climax of the last Harry Potter book, Harry Potter And The Deathly Hallows, which was released in 2007. Jack Thorne’s script is based on an original story by Thorne, Tiffany and Harry Potter author J.K. Rowling, who is heavily involved in the production.

Colin Callender
Marion Curtis/StarPix/REX/Shutterstock

Deadline’s final verdict will come tomorrow, after the gala opening, but the real question now is what the future holds for Harry Potter And The Cursed Child. Callender warns there are no firm answers — the creative team has been working tirelessly to get to opening night.

At midnight tomorrow night, the play’s script is published in hardback form and destined to become an instant bestseller. By next December, hundreds of thousands of tickets will have been sold to the play, which Callender says is best experienced for the first time onstage, but that’s a drop in the ocean of millions of Harry Potter fans worldwide.

A Broadway transfer seems inevitable, and Callender told me that was an ambition, also hinting that touring the play might be a way to go. The stagecraft employed is mind-bending but rooted in centuries-old sleight-of-hand techniques, so it wouldn’t be an insurmountable challenge to uproot. He refutes recent press speculation that plans are already in place for a North American premiere in Toronto. And one thing that seems least likely is a live cinema broadcast, the likes of which have been immeasurably popular in the UK and beyond — Callender insists that the show’s magic tricks work best in person and, having seen the play, it’s hard to argue with their astounding nature.

I sat down with him this afternoon at the Covent Garden Hotel in London — the place at which Tiffany was brought on board two years ago, and where the creative team gathered to celebrate last week as reviews started to come in.

DEADLINE: Has the play changed much during the preview period?

CALLENDER: There’s been a little fine-tuning of the script over the way, but no big changes. You never know, until you put a play up for an audience, whether it’s going to work. Things you think will work don’t, and things you’re not sure about work really well. I think we knew from the first previews that the show was in good shape, and that our job was fine-tuning it.

The other thing that was interesting is that we’ve had a series of workshops over the last two and a half years. The very early ideas that emerged as to how to stage certain sequences are on the stage now. Right from the get-go, the creative team knew what they wanted to do. Those first ideas, going back to the very first workshop, are still there, albeit finessed. It’s been a glorious process, and much more fun than it should have been.

DEADLINE: Well, the pressure of the anticipation must have been clear to you since before it was announced.

CALLENDER: Look, opening a new play in the West End is a challenge at the best of times. Opening two new plays back-to-back in the West End adds another level to it. Opening two new plays in the West End that happen to be inspired by the Harry Potter canon, with that added attention, added a whole new layer on top of all that.

My producing partner, Sonia Friedman, and I kept saying, “We have to look at this as if we were opening at the Royal Court. We have to forget all the hullabaloo and just focus on making this a great play. There was a moment in the workshops where we had a reading of the play — with some of the cast who are actually in the final production — just with the actors sitting around the table. By the end of it, a lot of us were in tears. Sonia and I turned to each other and said, “If the play works in an emotional and engaging way purely from what’s on the page, then what’s on the stage will be the icing on the cake.” If the play didn’t work as a play on its own terms, none of the magic, none of the special effects or theatricality of it all, would add up to anything. It all has to be rooted in Jack Thorne’s great writing.

10. Harry Potter and the Cursed Child, photo credit Manuel Harlan
Manuel Harlan

DEADLINE: There’s a beautiful scene between Harry and his son Albus, where Harry points out that he was an orphan and never had a father to base his own parenting on. Is that the heart of the piece?

CALLENDER: The original idea that Sonia and I had, that we took to Jo, was, what happened to the boy who lived under the stairs? What impact did that have on him as he grew up? We wanted to explore the emotional and psychological effects on that character, and how was he going to be a dad in a world where he wasn’t just an orphan, but he lived with the Dursleys in a tough situation, living under the stairs and not knowing who he was.

It’s moments like the one you just described where we stand at the back at the theatre and pinch ourselves, because it is those moments between a father and a son; or two 40-year-old men, talking about their lives; or a mother and a son; or two boys, struggling to grow up as teenagers. That’s at the core of the play, and those are two-character scenes with a bed or a chair and nothing else.

Those moments were at the heart of the ambition of the piece, and to see audiences relate to those moments has been very rewarding. The theater is a communal experience, and whatever the emotional connection between an audience member and the actors onstage, it ripples through the whole audience. Part of the fun of the play is being a part of that audience, both on the one hand if you’re a Harry fan — and everyone’s sharing all the revelations along the way — but also as an individual, whether you’re a father or a son or a mother or a daughter. There’s some way of relating to what’s onstage and everybody’s experiencing that together. It’s a very powerful thing.

DEADLINE: There was a big push, with hashtags and videos beseeching people to #KeepTheSecrets. The very first previews, on June 7 and June 9, felt special because this group of people was the first public audience in the world to be given access to this material. How has that changed through the preview period? It doesn’t seem like much has leaked.

CALLENDER: If you search hard enough you can find out pretty much everything. And amusingly, and ironically, the only media who leaked the story were two American websites. The British press has been brilliant. But actually, I don’t think people really want to know. Each audience varies. Last night, for example, was a riot. It was probably the most excited and excitable audience we’ve had since the beginning. They went nuts. Each audience seems to have a life of its own, which is why watching the show regularly is so exciting, because it’s always a different experience.

What’s really extraordinary is that we’ve never gone up late. That house is full at 20 minutes past the hour. Everyone’s in their seats and on the double days people are coming an hour and a half before the show goes up and queuing up. That audience wants to be there and get on with it. It’s fun.

25. Harry Potter and the Cursed Child, photo credit Manuel HarlanHP
Manuel Harlan

DEADLINE: You did a TV recording of the two-part Royal Shakespeare Company production of The Life And Adventures Of Nicholas Nickleby back in 1982, which was, at the time, a huge theatrical phenomenon. It’s hard not to note the similarities.

CALLENDER: Well actually, the approach to this, and the notion that the staging of the play should be raw magic and street theater rather than high-tech theater, was essential. It was why we approached John Tiffany about directing it, because that’s his background and it’s what he does. We didn’t use Nickleby as a model, but inadvertently, the echoes of Nickleby exist.

There’s a sequence in Nickleby where they built a coach out of tables and chairs and suitcases, and it didn’t inspire anything in this play, but it’s the same sort of idea behind how we do the Hogwarts Express. John Tiffany was asked how he was going to compete with the CGI of the movies, and he said, “Well, we’ve got the audience’s imagination, and that’s our secret weapon.”

One of the other big differences is Nickleby didn’t have a big cliffhanger. At the end of the first part of Nickleby, you could never return for part two. In this instance, you could just see part one, but if you did that, you’d be left hanging. It’d be like reading half a book.

DEADLINE: I couldn’t believe how many young people were filling a West End theater. Is the play encouraging new audiences to the theater?

CALLENDER: From our research, around 50% of the audience is first-time theatergoers, and I think about 60% of the audience are under 35. The play has to work for the super fans, and not speak down to them, and yet it had to play to those people who maybe had never read a Harry Potter book or seen the films. Walking that line was something Jack Thorne had to tackle. You can say this about the play, that it has to work on two tracks: the older, familiar characters, who are now adults, and the kids as well. One of the things that did score is that audiences of all ages seem to be enjoying it.

The core Harry audience now are in their late 20s and mid 30s and they grew up with Harry as kids. One of the things we learned during the previews was the extent you could follow the story or not, and from the audience response it seems you don’t need to have read the books or seen the films to follow the play. And again, that’s because it’s not about the plot. It’s about these characters, and the exploration of their relationships and inner lives.

DEADLINE: How long did it take to find Sam Clemmett and Anthony Boyle, who play the teenagers, Albus Potter and Scorpius Malfoy?

CALLENDER: Well, it’s been glorious working with John Tiffany because he had very specific ideas. In some cases he had actors in mind from very early on, and in other cases we had to go out and look for them. But he knew when he found them who he wanted. He was very clever about it, because on a couple of occasions he’d show us some auditions and stage manage the whole thing so we got to the place where he knew he wanted us to be. (laughs)

But casting this was a challenge. The whole endeavor was a challenge, because these actors had to establish themselves in their own right, knowing the audience was coming in having seen Emma Watson and Dan Radcliffe. Those guys have been brilliant, but our guys had to somehow get the audience from A to Z, from the books and the movies to the stage.

24. Harry Potter and the Cursed Child, photo credit Manuel Harlan
Manuel Harlan

I really do think that, in their own way, each one of them has made these characters their own. Within minutes I don’t think you’re thinking about other actors. They are those characters. It’s a great tribute to those actors. And it’s also helpful that they’re older. You never really spent any time with those three central characters as adults, in either the books or the films.

When Jamie Parker, who plays Harry, was asked about this, he said, “Well, I’ve played Hamlet, and many talented actors came before me in that role, but I had to make it my own and not be daunted by those other actors.”

But interestingly, I think at every step of the way we’ve looked at this play and said, “What can we compare this to?” Because it’s not a musical, and most stage adaptations of movies or books tend to be musicals. It’s not an adaptation of the existing books; it’s a new story. It’s not a single play; it’s in two parts. And it’s living in the wake of books and films. The combination of all that is unusual. It’s difficult to think of any other project like this. We were constantly coming up against decisions that had to be made where we didn’t have any reference points.

This extraordinary worldwide fan base is very protective of the canon, and we were very respectful of it and wanted to do right by it.

DEADLINE: How essential was J.K. Rowling’s blessing, oversight and creative contribution to helping that go smoothly?

CALLENDER: It was an enormous leap of faith on her part to entrust this to us all, and let us bring it to the stage. Sonia Friedman and I knew that she’d been approached about doing musicals and stadium-type shows, but we had this idea that there was a play in this idea of the boy who lived under the stairs. That was literally our starting point. We approached Jo’s agent, Neil Blair, and he liked what we said so we had a meeting with her at her offices in Edinburgh. It was a very emotional meeting in which we discussed all the themes in the books: death, grief, guilt, good versus evil and the power of love, family and friendship.

We didn’t talk story. We said, “There’s a way we can explore the characters onstage, freed up from having to work within the three-act movie constraints.” You can have scenes that run 10 pages. Scenes in a movie script rarely run more than a page and a quarter. Maybe three pages. But certainly not the 10- or 15-page scenes that we have here. That allowed us to have characters say things to one another that they couldn’t say in a page and a half. They go to places you can’t get to in a page and a half.

DEADLINE: What happens next?

CALLENDER: I’m genuinely not being evasive or coy, but we actually haven’t had discussions about transfers or anything. There’ve been stories about going to Toronto or whatever it is — nothing has been decided. No conversations have taken place yet. Frankly, we just want to get through this week.

We didn’t know whether the story would be spoiled. We didn’t know whether the press would break the embargo. It was around that that John Tiffany came up with the brilliant metaphor, saying, “Why would you open a kid’s Christmas present in November?” It was a great way of putting it.

Obviously we hope to come to Broadway. And there are Potter fans all over, so where else we go and when and how, I genuinely don’t know yet. But hopefully it will have a life and will be able to seen by people all over the world. Obviously that’s tomorrow’s conversation and not today’s.

DEADLINE: I’d love to see it on Broadway, if only to see how vocal the audience is. London audiences are usually incredibly reserved — even with something like Benedict Cumberbatch doing Hamlet — but the audiences for Cursed Child have been alive and engaged.

CALLENDER: That has been interesting. I live in New York, so I’m used to the audiences that cheer and clap through a play. It is unusual for London audiences.

22. Harry Potter and the Cursed Child, photo credit Manuel Harlan
Manuel Harlan

DEADLINE: It’s been great to see, because it’s much more in the tradition of theater going back centuries. But how much livelier can Broadway get?

CALLENDER: (laughs) I don’t know! It’s a good question.

DEADLINE: The idea of transposing this cast into a film is exciting, too, though probably further away. Are there any plans to do live broadcasts of the play into cinemas, like the ones the National Theatre have been doing?

CALLENDER: No, there have been absolutely no discussions about that whatsoever, and now that you’ve seen it you’ll know that part of the power of this is the experience of seeing it live, and seeing the magic performed live. Sitting there thinking, “How on Earth did they do that?” Part of the conversation in the intervals has been people debating how a sleight-of-hand trick was pulled off, and that’s part of the fun of the show. Not even my kids know the secrets. I haven’t even told them, and they’ve seen it 10 times already. (laughs)