The Secret of the Ginger Mice — Frances Watts

Alistair, Alex, and Alice have always been an inseparable (though not necessarily harmonious) triplet of mice...that is until Alistair is kidnapped one summer's night. While Alistair tries to make heads or tails of falling from the sky onto another young ginger-colored mouse named Tibby Rose (a most unusual incident on all accounts), Alex and Alice set off to find their missing brother. But in a world where spies abound and an elusive underground organization called FIG is only heard about in shushed bits and pieces, figuring out whom to trust is no small task for this intrepid trio. The key to the mystery seems to be within their grasp, but it only hints at another hair-raising adventure and creates more questions that seemed destined to remain unanswered.