a strange tale
When Walton resumes his narrative in Volume 3 (III:WC:1) his words will echo Victor's here, as he calls the narrative a "strange and terrific story" and acknowledges that the "tale is connected, and told with the appearance of the simplest truth," phrases suggestive of how broadly the judging of truth is an issue in the novel.
This phrasing also introduces the complicating factor of the novel's deliberately involuted structure. To adapt Walton's language, Victor's account of the strange tale occurs within his own strange tale, which has already conveyed the narrative of William's death provided by his father (as well as, in the chapter before, Elizabeth's account of local doings). This tale will be told twice more, in the courtroom (I:7:6) and in the Creature's autobiographical summation (II:8:33). If, in the end, readers can assume that they are able to sift the truth from its excessive narrative elaboration, the fact remains that in the official account Justine Moritz will be known as the murderer, and no one in Victor's family—including Ernest, who will presumably inherit a substantial fortune and the position that goes with it and his family's reputation in Geneva—will ever be any the wiser.