Source: http://www.novelguide.com/the-real-life-sebastian-knight/summeries/chap17-18
Timestamp: 2019-04-24 00:10:21+00:00

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On reflection, V. notices the similarity between the descriptions Paul Rechnoy (PahlPahlich in Russian) has given of his first wife, Nina, and that given by Madame Lecerf of her friend, Helene von Graun. Both women are shallow social creatures, cruel to men. Did they know each other at Blauberg? He feels the interview with Helene will be his last chance to find out this mystery and sends her a letter saying he will be at Madame Lecerf's in Lescaux on Sunday to meet her.
The large house at Lescaux looks rather shabby and worn out. He meets the husband leaving the house on his way to Paris for business. He shakes hands with V., saying his wife is waiting for him. V. thinks Madame Lecerf is pretty. She says her husband is kind but a bore. V. is impatient to see Helene, but Madame Lecerf chats with V. and then they go to lunch. Later in the garden, Madame Lecerf says she phoned Helene, and she was not at home. V. has a brief thought that he would like to make love to Madame Lecerf, though she gets on his nerves. He feels he is losing his grip. Just as she seems on the verge of manipulating him to stay at her house for a while, he takes a cane and draws in the dirt, saying it is a drawing of his brain waves. She banters that once she kissed a man because he could write his name upside down.
V. is struck by what she has just said, and then he makes a test. He utters a phrase in Russian that says there is a spider on her neck. She unconsciously screams and replies in Russian. At that, V. excuses himself and goes home. He realizes her hoax of pretending to be Madame Lecerf when she is really the Russian, Helene von Graun, and the former Nina Rechnoy. He had remembered that Paul Rechnoy's cousin could write upside down. He must have been one of her victims. Nina/Helene plays roles and enjoys seducing and fooling men. The mystery is solved.
Sebastian's last novel, The Doubtful Asphodel, was written without Goodman, Clare, or Nina. Sebastian was alone and dying, and that is the theme of the book. The reader does not know who is dying, but it is the consciousness in the book that is dying. The characters are but waves of his fancy that come and go, as he goes dark. On the threshold, however, there are rays of light.
V. had earlier compared himself to Sherlock Holmes solving a mystery and had even used a trick from those stories to gain information. In the garden scene as Helene (Nina) is about to seduce him, he becomes a detective again. She makes a mistake, referring to the man who could write upside down. She does not know that V. has already seen her ex-husband and his cousin. V. fools her into speaking Russian, proving that she is Helene and not her French friend.
V. comments on Sebastian's style that it reached perfection in his last book. The book replicates the process of death and going into darkness, yet there are gleams of light as to what is on the other side, “as if we are on the brink of some absolute truth” (Chpt. 18, p. 178). The author makes us believe he knows the truth about death. Things in life are not accidental, he realizes, but “a coherent sentence” (Chpt. 18, p. 179). As he is dying, things are simplified, and he enjoys seeing the world without the judgment of intellect. The author seems to die on the brink of truth and leave us with the puzzle of life yet to be solved, but V. says sometimes he feels the solution is hidden in Sebastian's last book. V. thinks it would not have been hard to translate into Russian. By this he implies that Sebastian's writing and themes have a Russian heart and soul. It is not the sort of art English readers would necessarily understand.

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