The Investigations of Mossa and Pleiti

The Investigations of Mossa and Pleiti is a novel series by Malka Older set in a human colony in the atmosphere of Jupiter. The stories are detective fiction in a setting both extraordinary and familiar.

Setting

Earth has suffered ecological catastrophe and become uninhabitable. An attempt to colonize Mars also made it uninhabitable. Centuries later, people live in artificial habitats, one particular set of habitats being in the atmosphere of Jupiter, which the colonists refer to as "Giant". A ring around the entire planet supports the habitats and links them via a rail system. One habitat hosts Valdegeld University, working to rediscover Earth's ecology so it can be reconstructed. Plants and animals from Earth are preserved and nurtured in another institution popularly known as the "mauzooleum". People live under an "atmoshield" and sometimes brave cold and winds wearing warm clothing and an "atmoscarf". Night and day are governed by Jupiter's 9 hour rotation, called a "diurnal". People choose which parts of a diurnal to use as their "day".

The main characters in the novels are two women, Pleiti and Mossa, who were lovers when younger but separated after quarreling. Pleiti is an academic in the Classics discipline, which tries to discover the relationships between species by studying old literature. Mossa has become an Investigator, an independent police agent. Most of her cases, and of the Guild of Investigators, are disappearances. These are a common occurrence on Giant, as people can simply step off into the atmosphere and fall into the planet.

Pleiti leads a cloistered life, doing her work and mentoring students. All her needs are taken care of in her rooms, very much like those of an Oxford don. Mossa is adept at gathering data and analyzing it, but Pleiti will see relationships that Mossa cannot.

Through the series, it becomes apparent that some factions are unhappy with the lack of progress made in reconstructing Earth's ecology, and are looking for ways to accelerate the effort. Others are threatened by such efforts, which may disrupt their comfortable lives.

Novels

The titles are quotes from one of the protagonists. After an chapter introducing the crime, the narrative continues in the first person from Pleiti's viewpoint.

The Mimicking of Known Successes

A man has arrived at a rail terminus, but never taken a rail car back from there. There is no evidence that he left the terminus by any means. His reported state of mind made it unlikely he committed suicide by jumping off. Mossa asks for Pleiti's help, since the man was a colleague at Valdegeld. Soon there is a murder, the victim seeming to be in the wrong place at the wrong time. Continuing the investigation may put Pleiti and Mossa themselves in danger.

The Imposition of Unnecessary Obstacles

Investigating another disappearance from Valdegeld, Mossa discovers that no fewer than 17 people of different backgrounds have disappeared. Mossa tries to find connections between them, and she and Pleiti go to the moon Io, where Mossa was born, to connect them through their families and political affiliations.

Awards and nominations

• The Mimicking of Known Successes was nominated for a 2024 Hugo Award for Best Novella.