"Dr. Hank Witherspoon has disappeared. When Jack and his genius siblings, Ava and Matt, find Hank's lab ransacked, they uncover clues pointing them to Brazil--but many questions remain. Why was Hank studying dangerous electric eels? And who is trying to steal his inventions? Their investigation leads them to a soccer prodigy, his savvy sister, a business tycoon who zips around on motorized boots, and a strangely incompetent riverboat captain. In the depths of the Amazon rain forest, the three siblings and their new friends must overcome deadly piranhas, stealthy jaguars, and the dreaded "Trail of Pain" to save Hank ... and make it out alive."--Page [4] of cover.