Netflix series The Final Problem plot explained

The Netflix mini-series ‘The Final Problem’, an adaptation of Arturo Pérez-Reverte’s novel, follows Benjamin Basil, a former Hollywood star known for playing Sherlock Holmes, as he becomes trapped in a series of murders on the island of Santa Águeda in 1959.

The central mystery involves a perceived suicide in a locked room. Through careful observation of inconsistencies, Basil discovers a complex identity swap: the woman initially found dead was actually the wealthy Adela Figueroa, while the woman surviving under the name Adela is actually Elisa Mander.

Elisa Mander had assumed Adela’s identity to escape her life as a typist and to seek vengeance against Hans Ludwig Klemmer, a German tourist with a past as an SS officer. The series concludes with Basil uncovering the truth behind the murders and the mechanical trickery used to simulate a suicide, though he ultimately chooses to remain silent about Elisa’s crimes.