Ibsen’s Ghosts is no longer shocking, just very depressing, which is what I most take from Frank McGuinness’ new “version” (who did the translation, then, eh?) directed by Iain Glen with wonderful Lesley Sharp as a fluttering Mrs Alving and startling Harry Treadaway as her stricken, haunted son Oswald.

Glen also plays the sneaky Pastor Manders which in this case is one job too many. His accent is curiously wayward, veering from Scottish Calvinist to Irish Episcopal, and the production, overall, is patchy.

Mrs Alving’s house, as designed by Stephen Brimson Lewis in grey panels and reflective windows, is curiously unlived-in, the architect’s model of the orphanage sitting on a side table like an exhibit.

In a play of ceaseless rain and sudden sunlight, sound and lighting by Richard Hammarton and Oliver Fenwick are too tentative, the stage continuously afflicted with rogue shadows, the rain sounding like the heating system in this very stuffy theatre.

The performances are similarly unfocussed, Sharp’s floating elbows and clear-eyed beauty giving way to strain and anxiety and, finally, a sort of gibbering intensity as Treadaway’s Oswald – who is shaking like a dervish from the start of the third act, and blackened after the fire like a chimney sweep – sinks into his syphilitic, epileptic coma.

Admittedly, if you’ve seen great mother/son turns like those of Irene Worth and Peter Eyre, Vanessa Redgrave and Adrian Dunbar, or Jane Lapotaire and Simon Russell Beale, this couple will pale in comparison. But only because they are playing the scene for maximum tacked-on hysteria and minimal emotional truth. You don’t feel like crying.

You don’t feel like laughing, either, although a programme note oddly suggests there’s a comedy lurking here. No sign of that, nor of any sexual might-have-been between Manders and Mrs Alving. Nothing seems embedded as this cast of fine actors skim nervously around the edges.

The chain of incestuous debauchery unleashed by the dead father, with his own son sniffing salvation in the feisty maid (Jessica Raine) who is his half-sister, and her father, the carpenter Engstrand (embodied with an oak-like ferocity by Malcolm Storry), planning a sailors’ whorehouse, is played as a matter of fact, not tragic misfortune.

It’s not clear, really, whether Regina is leaving to become a prostitute, or whether Mrs Alving will use the morphine tablets in an assisted suicide. The play just stops two hours after it started (one interval) without dragging you through the mire or leaving you drained, as it should.