Shadowfell by Juliet Marillier

Traveling through a freezing autumn, Neryn receives some help from the magical Good Folk. However, the help endangers Neryn and the Good Folk alike, for mistrust and fear rules the kingdom. Neryn also receives help from a mysterious stranger, but trust is not easy and his motivation is unclear. As Neryn continues toward Shadowfell, her survival depends on learning to trust others as well as herself.

Recommended for ages 13 and up.