Samuel Blink and the Forbidden Forest by Matt Haig.

Samuel has lost his parents right before his eyes in a freak accident and he and his sister Martha have now been sent to live with their Aunt Eda in Norway.  Eda lives in a remote area near a large forest.  She has several rules, but the most important one is that the children must never enter the forest.  Years ago, her beloved husband had entered the forest and never returned.   Plus, there are odd goings-on in the forest.  Strange creatures like trolls have been seen near it and huldres, grey-colored beings riding horses are sometimes spotted too.  When Martha is drawn to the forest and enters, Samuel feels he has no choice but to enter the forest too to save her.  In doing so, both children are caught in the evil created by the Changemaker, who has taken the forest’s friendly beings and converted them into evil by controlling their shadows. 

A fast-paced romp of a read, this book gallops along at a great pace, barely stopping for rabbit casserole before running on again.  The characters are lovingly written, and the writer’s asides within the book are charming and great fun.  Haig even takes great joy in creating rather horrific deaths and harrowing situations, a skill that older child readers will greatly enjoy themselves.

Recommended as a perfect summer read for children ages 10-14.