White Horse (Jess Bridges Mystery #2)
Joss Stirling

He suspects the young female victim may have been a member of the Children of the White Horse, a secretive valley commune, but none of the cult members are talking. That is until he discovers his friend, Jess Bridges, is undercover in the commune, attempting to persuade a wayward young woman to leave the cult.
Leo is confronted by the fact that Jess is heading right into the heart of a mystery that has less to do with ancient gods than it does modern vices, and there is nothing old about spilling blood…