Readers will need to tune their voices before meeting Troll, who guards the bridge leading to "the tastiest grass in the valley."When Vole arrives to cross, Troll sings a challenge in his clear, deep voice: "Troll-dee-roll, I'm a troll, / And my favorite food is vole. / With a knick-knack, paddywhack, / Better pay the toll, / or you'll end up in my bowl!" But hungry Vole can't pay, and the battle of wits begins. Luckily, Troll knows only one song, so Vole teaches him a new one. Three times, Troll gets so caught up in each new action song—children will recognize these storytime standards and join in—Vole teaches him that the anthropomorphic creatures successfully sneaks over the bridge for "a feast of grassy greens." But on Vole's fourth visit, Troll snatches him by the tail. Knowing he is destined for Troll's bowl, Vole begs for one last Troll song. In an unexpected twist, Vole joins "in with a sweet, high harmony," and together they fill "the valley with music so enchanting that fish [spring] from the creek, flapping their fins with pleasure…. Even the songbirds [hush] to listen." Understandably, as part of their new friendship, Vole insists on rewriting Troll's challenge song. Watercolor, colored pencil, and ink illustrations enhance the emotional subtext to this revised fairy tale. A harmonious twist on an old favorite with bonus action songs. 

—Kirkus Reviews