The uncertainties traditional in tales of espionage were extended in Dawn King’s Ciphers by a peculiarity of the casting arrangements in this production, under director Blanche McIntyre, for Out of Joint, Bush Theatre and Exeter Northcott Theatre.

Eight roles were apportioned to just four actors. As a result, some members of last week’s Playhouse audiences were not only unsure of what was being done in each of the short scenes of which this gripping play is composed, but of who was doing it.

Interval conversations I overheard revealed that a number of theatregoers were unaware, for instance, that Gráinne Keenan was playing two characters.

For them, the action must have been utterly baffling, since one of the parts was that of dead British spy Justine and the other that of her feisty sister Kerry who was out to prove that her ‘suicide’ was nothing of the sort.

Such confusion was made possible, first, by the fact that the women looked and dressed alike and, second, by time shifts in the action that regularly brought Justine back from the dead.

Through rigorous concentration (such as any critic should give!), I felt confident I was following what was going on. But the denouement utterly threw me, as it must presumably have thrown everyone else. Sometimes the ‘doubling’ worked to interesting effect — Shereen Martin, for instance, as both Justine’s no-nonsense controller and the equally brittle money-bags wife of her young artist lover Kai (Ronny Jhutti).

The spy’s complicated private life turned out to be intimately involved with her fate. This also featured a second lover in the shape of the Russian Koplov (Bruce Alexander) whose role in the story was completely misunderstood by your reviewer.

But giving misleading impressions seemed to be the name of the game here.