A fine dark line - Joe R Lansdale

It is the summer of 1958 in Dewmont, Texas, a town the great American postwar boom passed by. The kids listen to rockabilly on the radio and waste their weekends at the Dairy Queen. And an undetected menace simmers under the heat that clings to the skin like molasses. . .
For thirteen-year-old Stanley Mitchell, the end of innocence comes with his discovery of the mysterious long-ago demise of two very different young women. In his quest to unravel the truth about their tragic fates, Stanley finds a protector in Buster Lighthorse Smith, a black, retired Indian-reservation cop and a sage on the finer points of Sherlock Holmes, the blues, and life's faded dreams.
But not every buried thing stays dead. And on one terrifying night of rushing creek water and thundering rain, an arcane, murderous force will rise from the past to threaten the Stanley and everything he holds dear.
Vintage Lansdale, A FINE DARK LINE brims with exquisite suspense, powerful characterizations, and the vibrant evocation of a lost time.