"Bismuth subsalicylate and stimulants," she muttered to herself. "Counteracting stomach upset and livening us up, but getting it all wrong." She frowned, and opened a database window. "Bismuth subsalicylate - bismuth subsalicylate - I'm wondering if it's the counteragent for something we don't know about. Has Science cracked open any interesting alien artifacts recently? Anyone break into a sealed tomb in the City and release a terrible curse?"

She's only half-kidding; over the years all sorts of threats have been uncovered on Stacy, many of them invisible to the AI herself. It would be just like her current pattern to start dosing the crew with something to repel giant flesh-eating slugs without telling them that hey, giant flesh-eating slugs were loose.