In a dramatic cold open, Caldecott Medalist Santat renders the catastrophic sinking of an ocean research vessel: marine biologist and captain Michel Revoy goes down with the ship, leaving behind a labeled canister and message in a bottle, but his brother Paul survives, charged with caring for Michel's daughter, Sophia (all are portrayed as pale-skinned). Five years later, a figure in an antique diving suit wades onto a busy San Diego beach; it's a robotic aquanaut, captained by four intrepid sea creatures—a hermit crab called Sodapop, octopuses Antonio and Carlos, and an unflappable sea turtle named Jobim. They've encountered Michel's diary, and they're searching for Aqualand, the marine reserve the Revoy brothers founded. The sea creatures are effective comic foils for a human drama about family legacy and Aqualand's commercialization, and they also carry the story's moral arc as they risk their lives to rescue their captive brethren, encountering Sophia along the way. Kinetic panel artwork impresses throughout, with smart pacing that swings between hilarity and suspense—the underwater scenes in particular mesmerize with saturated blue-blacks that convey infinite depth and silence. Ages 8–12. Agent: Jodi Reamer, Writers House. (Mar.) ¦

Gr 3–7—A tragic accident at sea claims the research vessel Miette and the life of its captain, renowned marine biologist Michel Revoy. Five years later, Michel's brother, Paul—also a marine biologist—is attempting to keep their research alive while raising Michel's daughter, Sophia, when Paul and Sophia make a shocking discovery: four of the sea creatures from the Miette have resurfaced! Disguising themselves as a human in Michel's old diving suit, the creatures search for safety at the Revoy-founded Aqualand marine reserve. Marigold and tangerine-orange coloring contrasts with shades of teal to help set the story's mood, which rotates between the light, comedic high jinks of extremely intelligent sea creatures and somber moments of loss, empathy, and understanding. Santat expertly uses numerous two-page spreads to provide a sense of scale, both to the various creatures and humans as well as to the world they are trying to navigate. In a story that requires some suspension of disbelief, it's the sea creatures who provide the most depth in their characterization as they overcome fear for their own safety to support those around them, leaving the humans to follow their lead toward a more just world. Multiple time jumps keep the story moving forward after big reveals, and back matter includes a creator's note and character sketches. VERDICT An endearing tale of love, loss, and the value of family—biological and found—this is recommended for readers who want gentle inspiration to do what is right, even if it involves compromise or sacrifice.—Alea Perez