WILLIAM Nicholson’s play is based on the real-life relationship between author and academic CS Lewis and the American poet Joy Gresham, and it is a powerful, thought-provoking piece that can, and probably should, leave its audience feeling almost shell-shocked.

Patricia Richardson’s production is stamped, as always when she directs, with the hallmark of quality, both in the attention to every detail and in the extraordinary performances that she gets from her cast.

Matthew Ellison (Lewis) is every inch the “foolish, frightened old man” that he describes himself as to the dying Joy Gresham, played with intensely moving emotion by Tanya Alexander.

These are characterisations that I cannot believe could be bettered anywhere, and I can give no higher praise than to say that I believed in them utterly.

Mike Griffiths too is superb as Warnie Lewis, and young Ben Winkley gives an appealing portrayal of Joy’s son, Douglas.

Props are first class, as is the set, designed by Vicci Johnson, which doubles as a number of places although is essentially Oxford college rooms. And the rear wardrobe, the doors of which open to reveal Narnia, is beautifully created.