The Dark Beneath the Pines — Anne Eliot

The Summoning.

Lovely young Andrea Wilmot hadn't wanted to return to the lavish summer place, not with her beloved uncle dead and the memories of their joyous summers still so painfully clear. But she could not refuse her family's summons. Before her uncle's mysterious drowning, his entire fortune and been hidden away, and now Andrea must add her cool intelligence to the family's desperate theories about its hiding place.

But the search would involve much more than detection. Much more than Andrea or anyone dared imagine. For suddenly in the sweet, dark mist of the pine forest, Andrea found that a dead man could come alive, a friend could become an enemy.