"A delightful combination of race-against-the-clock medical mystery and outwit-the-bad-guys adventure." - Publishers Weekly, Starred Eel has troubles of his own: As an orphan and a "mudlark," he spends his days in the filthy River Thames, searching for bits of things to sell. He's being hunted by Fisheye Bill Tyler, and a nastier man never walked the streets of London. And he's got a secret that costs him four precious shillings a week to keep safe. But even for Eel, things aren't so bad until that fateful August day in 1854 - the day the deadly cholera ("blue death") comes to Broad Street. Everyone believes that cholera is spread through poisonous air. But one man, Dr. John Snow, has a different theory. As the epidemic surges, it's up to Eel and his best friend, Florrie, to gather evidence to prove Dr. Snow's theory - before the entire neighborhood is wiped out. "Hopkinson illuminates a pivotal chapter in the history of public health. . . . Accessible . . . and entertaining." - School Library Journal, Starred "For [readers] who love suspense, drama, and mystery." - TIME for Kids