The Investigation

The Investigation (original title Śledztwo) is a science fiction/detective/thriller novel by the Polish writer Stanisław Lem. The novel incorporates a philosophical discourse on explanation of unknown phenomena. It was first published in 1958 in "Przekrój" magazine (issues 698-711) and in 1959 as a book by the Publishing House of the Ministry of National Defense (Wydawnictwo Ministerstwa Obrony Narodowej).
Plot.
The novel is set in London. A young Scotland Yard lieutenant Gregory investigates the mysterious disappearances of corpses from London morgues to reappear somewhere else. The only "explanation" is an abstruse statistical theory that correlates the body snatching with local cancer rates. The detective suspects the statistician Siss who came up with the theory of being the perpetrator. In reality it appears as if the corpses "resurrect". Gregory suggests that the corpses are being infested by certain microorganisms, which have some kind of collective intelligence. Siss ponders upon this and thinks that this phenomenon existed for a long time and may explain the belief in resurrection in many religions. Eventually all was explained as a highly unlikely coincidence of several factors. However it turns out that some cases do not fit...
Discussion.
In "The Investigation" the classic procedural police mystery is turned into a metaphysical puzzle, with Kafkaesque themes. As in almost all Lem's production, philosophical and epistemological questions are presented under the simple surface of the plot: what is the role of scientific inquiry? What does the existence of competing explanations mean for that goal? The novel also introduces a theme that will later be present in Lem's works, in particular, in his major essay, "The Philosophy of Chance": that observations are formed by the properties of the observer's mind, rather than by any properties of the observed.
Lem wrote that he received many angry letters from readers who demanded an explanation how corpses can move.
Adaptations.
In 1970s the novel was put on screen in Poland twice.