Just as in the previous The Adventures of Grandmasaurus (2020), a sparkle of special dust sets Grandma, the class chaperone on the field trip to the aquarium, to sneezing, and each blast transforms her into a different prehistoric creature. This time, in line with the locale, the creatures are big marine reptiles or fish—all syllabically identified, from “Sho-ni-saur-us” to “Meg-a-lo-don,” and drawn in the cartoon illustrations with reasonable accuracy…aside from their large glasses, twinkly eyes, and distinctive curls of blue hair anyway. Human Grandma and her frantic granddaughter, who serves as narrator, present as White, but the rest of the class and their task-oriented teacher, Ms. Priya (“Observe and learn, my dear leaders of tomorrow”), are representatively diverse of hair, skin, body type, and mobility. As the class troops past big aquaria and sandy outdoor pens, cautionary notes about leaving live coral and turtle eggs alone and even disposing of litter properly swim alongside quick overviews of what aquatic rescue centers are for. A closing gallery of the 11 creatures Grandma becomes before her final restorative sneeze provides both a recap and a few more basic facts about each.