A few years ago I attended a stage adaptation of C.S. Lewis's The Screwtape Letters that was touring the country and came locally. Now the same people have adapted his The Great Divorce.
The Great Divorce is a much less well-known book, but I think a more powerful one. Its critiques of human self-delusion get under my skin more than Screwtape's do. It's in the form of a narrative in which Lewis dreams that he accompanies ghosts from Hell - which he depicts as a drab, ugly town stuck in an eternal twilight - on a bus trip to Heaven, where the spirits there (often past earthly friends of the visitors) try to persuade them to cast off their delusions and transform themselves into heavenly residents - and occasionally succeed.
The point is that whether you return on the bus or not, and even whether you take the trip at all, is entirely voluntary, and as this trip is an allegory for accepting spiritual humility, it's a struggle in the minds of those who have to decide whether tis better to reign in Hell than to serve in Heaven (a line quoted in the book). Lewis's Big Idea here is that Hell is only Hell if you stay there; if you leave, it was Purgatory all along. God doesn't sentence people there; they commit themselves there of their own self-righteousness. God is just waiting for them to repent, which means giving that up.
I don't know how theologically orthodox this idea is, but if it is, it offers a complete rebuttal to the "God is evil because he sends people to Hell" theory, one of the few times Lewis really strikes home. (There is, here, no torture in Hell, just a complete drabness and people totally wrapped up in themselves, assuming you don't call that torture.)
I don't know if I've conveyed this. If it seems nonsensical, read the book. It's very short.
So, the play. It was about 75 minutes long, no intermission. Most of the book was there; the Dwarf and Tragedian were the most conspicuous omission. Three actors, two men and one woman, played all the incidental roles of spirits and traded off the part of Lewis (as character and narrator). Quick costume changes helped convey this, and I guess it was to make clear to the audience that they'd all be Lewis that the frame narration began with all three speaking, and moving, in unison while identically costumed (as dons in tie and sweater). This was risibly reminiscent of the scene with the three burglars in Noises Off.
One of the male actors, though good, was flop-sweaty in that "Hey, I'm acting here!" way. The other man was smoother but didn't differentiate his characters. The woman, Christa Scott-Reed, was by far the best: she played three supercilious women in the course of the play (Lewis had a bug on about that kind of woman: they show up throughout his fiction) and made them all different.
The scenery was portrayed through elaborate back projections (and a lot of REALLY LOUD background noises, a feature of the Screwtape as well), and this reliance on technology gave rise to the weirdest moment. There's a scene in the book where one of the ghosts is trying to pick up one of the heavenly apples to take back (the ghosts are insubstantial, and Heaven is so intensely real that the grass cuts their feet - something the actors, who performed barefoot, constantly remind you of). The voice of an angel admonishes this ghost.
In the play, the angel's voice comes amplified from above. The weird moment occurred in the previous scene, where the same voice, with the same amplification, interrupted the play, addressed the one actor then on stage by name, and told him to leave the stage momentarily. The house lights came up. Was it a medical emergency in the audience? No! The computer that directs the backdrops had frozen, and they had to reboot it. As Lewis could have told them, put not your faith in technology.