Mexican Gothic

After receiving a frantic letter from her newly-wed cousin begging for someone to save her from a mysterious doom, Noemí Taboada heads to High Place, a distant house in the Mexican countryside. She’s not sure what she will find—her cousin’s husband, a handsome Englishman, is a stranger, and Noemí knows little about the region.
Her only ally in this inhospitable abode is the family’s youngest son. Shy and gentle, he seems to want to help Noemí, but might also be hiding dark knowledge of his family’s past. For there are many secrets behind the walls of High Place. The family’s once colossal wealth and faded mining empire kept them from prying eyes, but as Noemí digs deeper she unearths stories of violence and madness.
(goodreads.com)