I am currently halfway through listening to the excellent audiobook version of CS Lewis's That Hideous Strength ('THS'), read by Stephen Pacey (who played Del Tarrant in the excellent 1970s BBC Sci-Fi series Blake's 7).
From a perspective and through a lens derived from CS Lewis's best friend Owen Barfield; I can imagine a revised version of THS, in line with my understanding of our situation some seventy years on from the publication of THS in 1945...
One major difference would be that Lewis has his heroes (the St Anne's fellowship) essentially passive in their obedience to orders coming from the 'angelic' helpers. Nowadays, we would not receive these orders. We would have-to work things out for ourselves, as best we could. Or, more exactly, we would need to develop the spiritual perspective and abilities which would enable this working-out. We would need to develop what Barfield termed Final Participation.
Final Participation is something which can only come from the choice and will or each of us, as individuals. It cannot be conferred upon us - indeed the essence of it is that we are free and agent. Final Participation is precisely a personal, experiential effort-full thing. We need to look-within to seek god-in-us, to find our divine self - and to become aware of this.
Here and now - we aren't going to be able to wait or hope for leadership; probably we will be literally on-our-own: alone... at least in many practical respects. This because our current situation is not a recapitulation of monasticism or the like; the destruction, subversion and inversion of groups is at the heart of the evil of our modern condition.
A modern THS would perhaps be about the good characters, the heroes of St Anne's, individually and dispersed. About moral choices made alone and in the context of an overwhelmingly large and powerful Establishment of Evil that is not recent (like The NICE in THS), but has been in place and in control for at least two generations.
The angels ('eldils') would not be perceptible in the necessary state of consciousness of Final Participation; they would not visit, we could not see them - and neither would we hear them speak in words; not even words formed in our minds. Instead, angels would communicate directly by joining their thinking with ours.
However, we - in our thinking - would always be free and agent - in control. Hence we could block contact with the angels, if we chose. And we could not (merely) open our minds to them. Rather, we would actively be thinking is such a way that we could share in their thoughts, and they in ours.
How could help come? In defeating a vast and powerful evil Establishment, clearly help is essential. THS had the Original Participation magic of Merlin, and direct and miraculous aid from the eldils/ angels. What might we have, now?
Well, it would be imperceptible to direct observation. It would be behind the scenes - by synchronicity. Natural phenomena (rain, wind, sun, tides, earth movements...) would - 'coincidentlally' - favour Good and be hostile to evil.
Enemies would be repenting (as the situation clarifies) and changing sides, ceasing to do their evil duties, turning to sabotage the evil plans.
There would be events of exceeding improbability - actually miracles, but always explicable in terms of chance. Perfect-Storms of 'luck' - both good and ill 'luck' - good fortune for the Good and adverse chance for the evil. Cumulatively piling-on, and on.
(These being proximal consequences of distal and subtle angelic interventions; behind-the-scenes changes of arrangements; altering small upstream occurrences to generate large downstream effects...)
How about our own personal strength, motivation, will - and love? How could these be sustained when we are on-our-own? I assume there will be positive-feedback reinforcements of such things. As the situation develops, evil becomes clearer, becomes un-masked. Because evil is a trial of our strength and a mode of spiritual development; it may be like exercising in a gym - immediate effort being rewarded, some time after, by greater strength.
The key and core is motivation; the guiding principle is honesty; and the goal is love (towards which we are pointed by the discernment of the heart; which knows truth, beauty and virtue - and their opposites).
We must be self-sufficient in terms of motivations; but this is only possible through the gift of repentance from Christ. Trial and error will get us where we need to be; but only when error is acknowledged and repented.
The war is between those who acknowledge and experience the spiritual world, the immaterial world, the world of God; and those who don't. Between those who know we are all children of God and destined to become free; and those who believe themselves and everyone else to be evolved automata subject to rigid determinism alleviated only by randomness. Between those who take ultimate responsibility and look to god-within; and those who hope for external intervention for rescue.
The happy ending of a new THS would be very happy indeed! A world of free, agent, people affiliated in loving families and with close friends; a world therefore open-ended, of creativity. Not a utopia; but an active, developing, expanding, deeply-rewarding world of perpetual interest, challenges, increasing awareness and understanding - making, doing and thinking.