I am a huge fan of immersive theatrical experience, the kind of thing where you have to follow the actors around from room to room, and may be drawn into actual interaction. I love it because what it does can only be done live, and, for any art form, particularly a perennially-threatened one like live theatre, that’s a key question to ask up-front: why this form. What kind of experience am I offering, and why can’t my audience get that experience more cheaply, more conveniently, more effectively some other way. The proscenium of the 19th century may have made sense in its time, but even the great plays of that era come to life when that convention is ignored - when you stage The Pirates of Penzance as an Annette Funicello beach party to which we’re all invited (the show is being revived in Boston later this month – go see it!), in a production of The Cherry Orchard, you have Charlotta chat with the audience, and even hand someone a bowl of soup to hold; or, in a production of Ibsen’s Enemy of the People, you put the angry townspeople in the audience for the town hall meeting, so that when Doctor Stockmann goes on his rant he’s insulting not just them but us; and so on. The difference between the magnificently intimate film, “Vanya on 42nd Street,” and an in-your-living-room production of Uncle Vanya like the one recently staged by Soho Rep, is that, even at its most intimate, film keeps us safely in the position of the voyeur, whereas live theatre, at its best, draws us out of our seats, and onto the stage.

Immersive theatre makes this its fundamental principle. The king of the genre is Sleep No More, which I saw a couple of years ago (I re-posted my review apropos of its imminent closing – see it while you can). But you don’t have to take over a warehouse to do this kind of theatre, as the folks at Third Rail are proving every day at the Kingsland Ward at St. Johns in Williamsburg, with Then She Fell, an immersive theatrical experience based on Lewis Carroll’s Alice books and, more specifically, the author’s real-life relationship with the girl, Alice Pleasance Liddell, who inspired the main character of those books.

The show is set in a hospital ward. The tiny audience – no more than 15 per night – gathers in a waiting room, and then are led into the facility one by one. And, one by one, we are introduced to the peculiar inmates of this sanatorium: Lewis Carroll (Alberto Denis on the night I saw it – the cast varies night to night), a pair of Alices (Rachel Berman and Marissa Nielsen Pincus), the White Rabbit (Niko Tsocanos), The White Queen (Jennine Willett), the Red Queen (Jessy Smith), and the Mad Hatter (Elizabeth Carena).

When they are together, they engage in ritualized dances: the Red Queen teases and torments the White Rabbit, trapping his head in a chair, decapitating his half-white, half-red roses; the White Queen releases Alice’s hair, and teaches her to release herself physically as well. The Alices mimic each other across a “mirror” of empty air, then invite us to mimic them, and then (in another scene), mimic each other again through a one-way mirror of glass. Lewis Carroll dances with Alice up and down and around a staircase, yearning to take her in his arms, then finally doing so. The culmination of the dances is a mad Tea Party that the audience perforce must join, comically failing (in my case) to mimic the rituals of tea pouring/drinking/tossing and repeatedly shifting seats, a particularly effective bit of theatrical mayhem (and one of the few bits that directly mirrors an episode in the books, as opposed to alluding them).

When they are alone with us, the characters are more inclined to speak. Sometimes they ask you to take dictation for a letter. The Mad Hatter wants her hat back; when you’ve finished her letter, she stamps it and tosses it in a drawer with dozens of other copies. Lewis Carroll wants a last chance to say goodbye to his beloved Alice; when you’ve finished his letter, he takes it, removes his shoes, steps off the slatted wooden path into the water, then rolls the letter up in a bottle and sets it down to float away. Other times they tell you stories – the White Queen may lay you down on a bed and tell you a bedtime story, about a girl who lived backwards, so that, when she first met her beloved, she knew all about their relationship to come, and was already bored of him; and by the end, when he had grown to love her deeply, had already forgotten nearly all about him, until, after their last day together, he was a stranger to her. (This last was my favorite bit from the show – possibly I like being told stories in the dark, or possibly I just like being told to lie down in bed with strangers.)

Then She Fell is more intimate than Sleep No More – only 15 members of the audience, and the action is played out in a much smaller space – but also more stately and controlled. Unlike Sleep No MoreThen She Fell takes pains to make sure you actually do experience what they intend you to – you don’t wander; you are led. Which leaves you more time, as a member of the audience, to meditate on what you are seeing. You don’t have the anxiety about missing something happening elsewhere in a vast and maze-like space, but you also don’t have the urgency of needing to discover something. You can think, in real time, what does this mean?

My meditations traveled along a winding path. First, I thought about the age of the Alices. They are played, in the production, by adults. Ms. Liddell, meanwhile, was all of eleven years old when her relationship with Charles Dodgson was broken off by her formidable mother (I wondered whether the two Queens were two versions of this maternal spirit, the Red Queen fierce and domineering, the White more nurturing). That break may possibly have been occasioned by a proposal of marriage from the 31-year-old Dodgson (or there are other possibilities, such as that he was courting her governess – all answers are speculative). Within the world of the play, it’s very likely something like an inappropriate romantic overture was the cause of the rupture. By casting adult women to play Alice (though they are dressed as Alice from the books), the scandal of such a proposal is blunted, to a degree.

But the title of the piece is Then She Fell. Whether down the rabbit hole into insanity, or into love, we are concerned primarily with her trajectory, not with his. And her trajectory is towards adulthood. So I wondered: are we seeing Alice falling, well after she no longer knew Dodgson, for the man who had fallen for her before she could reciprocate? Is that the point of the “girl who lived backwards” story? Is this a theatrical counterpart to the movie, “Dreamchild,” in which Alice Hargreaves (nee Liddell) comes to grips, as an 80-year-old woman, with the story that colonized her identity as a young girl, and with the man whose love prompted him to plant that powerful seed in her young mind?

I thought about the hospital setting. What disease is being treated in this facility isn’t immediately clear – there are a lot of references to malaria on the walls, but none of the action revolves around that malady. As the tour goes on, it becomes clear that the malady being treated is, in fact, Carroll’s love for Ms. Liddell. And, after a century and a half, the cure still isn’t effective. Is this a comment on our tendency, as a culture, to medicalize abnormality? Most of us would look at a Dodgson, if we knew one, and say: he needs treatment. And we might well be right – but by how much would our understanding of his mind fall short if that was all we learned. By the same token, most of us would look at an Alice, if we knew one, and understand her in terms of trauma: how was she affected by the (emotionally) inappropriate attentions of this older man at such a young age – and is there a therapy that will help her get over it. But, again, by how much would our understanding of her mind fall short if we did not reckon with the importance, in all dimensions, that such an experience would have had for her?

Or is the piece ultimately about us and our experience (as immersive experiences are particularly apt to be)? We, the audience, are people who chose to be immersed in an Alice experience. The books already mean something to us – they have already colonized our minds. They are artifacts of our childhoods that have continued to affect us as adults, to bring us back to a state of childhood excitement, or to reflect on our distance from that state. Is that the love that we are supposed to recognize on stage, the love that this institution is trying, ineffectually, to cure us of? Are we Alice? Or, better, the Alice-Carroll duet, playing out a loving dance with our own childhoods, with childhood itself?

Then She Fell is, among other things, a hipster artifact: staged in Williamsburg, exclusive (only 15 audience members at a time), immersive, drenched in Victoriana – and, most important, in the props and signifiers of the gifted child. Because from Dave Eggers to Wes Anderson to whoever else you care to name, this culture is created by and for adults who were and still are gifted children. They were adults early, reading tougher books and understanding more than they ought of the adult world’s emotional complexities. And they remain children late, turning work into games, obsessed with the outward signs of self-creation, living by the golden rule of playing nice. And if you’re looking for a subject to exemplify that cultural nexus you can’t really beat the Alice books.

Late in the play, as I experienced it (different members of the audience go through scenes in a different order), I found myself outside a white room, gazing through a window past rows of medicine bottles. Inside the room, the Red Queen raged and fretted, throwing off her mantle with its fierce red frill, berating herself for something. Then she invited us in, and sat at a vanity where she adjusted her makeup, and told us a story – a story of how you have to control your passion to achieve any measure of power in this world. At the end of which she reassumed the mantle of the Red Queen, and led us out to exit the performance.

I had, prior to that scene, been thinking of the Red Queen as possibly a reference to Alice Liddell’s domineering mother, possibly a reference to Dodgson’s perceptions of a certain kind of female power. But now, I thought of her as a possible destination in adulthood for Alice, and for us – a reference to how one might deal with the madness of love, by subordinating it to power and control. And, as it turns out, her strategy didn’t keep her out of the same asylum where they keep the White Rabbit.

How to avoid being trapped there ourselves? I couldn’t say for certain – but I would recommend, as a first course of treatment, going to the theatre.

Then She Fell will be performed at The Kingsland Ward at St. Johns in Williamsburg, Brooklyn, through September 29th.