An old sanatorium. A terrifying murder. Six suspects and a case that never closed . . . Discover the new locked-room mystery by the Sunday Times bestselling authorOnce a hospital dedicated to treating tuberculosis, The Akureyri Sanatorium now sits haunted by the ghosts of its past. But a single wing remains open, housing six employees.When one of the hospital's nurses, Yrsa, is found brutally murdered, it sets in motion a series of terrifying events.Despite just six suspects, the case remains unsolved two decades later. Until young criminologist, Helgi Reykdal, attempts to put the mysteries of the hospital’s past to rest . . .