Daisy Thistledown and her Greenwild cohorts seek help from hostile water magic folk to fight the rising tide of environment-destroying Grim Reapers.The grown-ups may have their plans to relieve the beleaguered enclave of Botanists (including Daisy's mother) who are lost in the Amazon rainforest, but it's up to Daisy and her young fellow fledgling Botanists of the Five O'Clock Club to save their bacon once again. Daisy and friends-animal whisperer Indigo, the brainiac dubbed the Prof, and doughty Acorn-are joined along the way by Max, a fugitive with a hidden past and a distinctive facial birthmark. They face multiple ambushes mounted by the murderous Reapers who leave bleached coral and plants in their wake. Along with riding magnificent water horses and rescuing a menagerie of rare creatures from an animal market, the young folk learn both how to trust one another and how to control their individual magical gifts in time to scupper a usurper's evil scheme and enlist needed aid for the climactic conflict to come. Paganelli's flourishes of spot art and monochrome views of magical beasts and the racially diverse human cast add elegant accents to this bustling middle episode. More experienced genre readers may not find many surprises in the plot but will enjoy the adventure nevertheless. Daisy's mother is Persian, and her late father was English.Awash in magical exploits and creatures. (Fantasy. 9-13)