Masks Within Masks

(This cover depicts a specific scene in the novel, on p. 475 of the edition quoted here.)

"'Aycharaych...Who else? Masks within masks, shadows that cast shadows...Merseian operatives posing as Esperancians posing as Dennitzans whose comrades had formerly posed as Avalonians, while other Merseian creatures are in fact the Terran personnel they claim to be...'"
-Poul Anderson, A Knight Of Ghosts And Shadows IN Anderson, Sir Dominic Flandry: The Last Knight Of Terra (New York, 2012), pp. 338-606 AT p. 503.

At this point (but only at this point), I suddenly feared that A Knight Of Ghosts And Shadows was itself rather insubstantial. And it would have been very insubstantial if it had consisted only of "...Merseian operatives posing as Esperancians posing a Dennitzans..." etc - a corridor receding to nowhere. However, this paragraph is both a summary and a sign. In the multiple deceptions, Flandry recognizes the signature of Aycharaych and that being's tragedy, as revealed in the novel's culmination, is substantial indeed.

Five planets are named here: Merseia; Esperance; Dennitza; Avalon; Terra. Three more are implied:

Chereion, home world of Aycharaych;
Ythri, from which Avalon is partly colonized;
Diomedes, where this multi-layered deception is perpetrated.

All eight have substantial stories in the series. Only two are told in the current novel. But Chereion has been prepared for in earlier installments. And a lot of details are given about Dennitza. Further, this planet is connected to the previous episode because it replaces Vor as capital of the Taurian Sector.