The story is set in the small, foggy Galician town of Merlo , a place physically and emotionally isolated.

Emma Cruz , a lawyer and professor of criminal law, moves to Merlo to teach at the university while trying to escape her own personal heartbreak.

Her arrival coincides with the 25th anniversary of the disappearance of the Giraud sisters (aged 6 and 13), who vanished without a trace in 1994.