She reappears in "The Penultimate Peril" where she is staying at Hotel Denouement in room 371 with Vice-Principal Nero and Mr. Remora. Mrs. Bass was wearing a thin black mask and a small white wig as a disguise. It is implied, as foreshadowed in "The Austere Academy" and "", that she has robbed a bank, having in her possession several bags of money marked with name of Mulctuary Money Management. It is also implied that the money she stole is from the Spats Fortune. She makes no attempt to conceal her crime from Vice Principal Nero and Mr. Remora and they in turn do not judge her, seeming to look on her robbery as an everyday occurrence. She also reveals that her invitation to the cocktail party hosted by "J.S." which asked her to bring all her valuables and since she did not earn enough as a teacher to have valuables, she was forced to turn to a life of crime which Nero mimicked. Mrs. Bass stated that her invitation stated that there will be a party to celebrate the metric system. When being served by Hal at the Hotel Denouement's Indian restaurant, Mrs. Bass orders 10 grams of rice, 1/10 of a hectogram of shrimp vindaloo, a decagram of chana aloo masala, 1,000 centigrams of tandoori salmon, 4 samosas with the surface area of 19 cubic centimeters, 5 deciliters of mango lassi, and a sada rava dosai that is 19 centimeters long. Despite her defense of the Baudelaires in "The Austere Academy" when their own identities are revealed at the Hotel Denouement following the death of Dewey Denouement, she claims that they are criminals that should be punished. During the blindfolded trial, Mrs. Bass submits the blueprints for banks and later claims that the Baudelaires robbed a bank to which Mr. Poe quoted "Who said that?" When Count Olaf starts a fire at the Hotel Denouement, Mrs. Bass was last seen on the third story muttering something about a getaway car.