The novel “Mostly Harmless” by Douglas Adams was published for the first time in 1992. It’s the fifth novel of the so-called trilogy of five books and follows “So Long, and Thanks for All the Fish“.

Arthur Dent and his beloved Fenchurch are traveling through the galaxy but in the course of a leap into hyperspace the girl disappears. Arthur tries to understand what happened and is explained that the phenomenon was caused by the fact that they were coming from an unstable sector of the galaxy. Arthur has no choice but to travel alone.

Ford Prefect is back to the offices of the Guide, where he discovers that the publisher was bought by the mysterious InfiniDim Enterprises. To his horror, he discovers that the Vogons are behind the new property and he can only run away while trying to save a new version of the Guide.

In an alternate universe in which the Earth wasn’t demolished by the Vogons, Tricia McMillan is contacted by a group of Grebulon aliens arrived from a base on the tenth planet of the solar system. They don’t know their origin because their computer and even their personal memories have been corrupted so the only part of their mission they know is to look at the most interesting things in the solar system.

Several years after the publication of “So Long, and Thanks for All the Fish”, Douglas Adams returned to the “Hitchhiker’s Guide to the Galaxy” series with a novel very different from the previous ones. The series was already quite diverse in terms of the kind of stories told and the fact that they were focused on different protagonists but in “Mostly Harmless” there’s also a different tone.

In the previous chapters of the “Hitchhiker’s Guide to the Galaxy” series, the plots were sometimes a bit vague and seemed more like sets of sketches, jokes and sometimes philosophical considerations. In “Mostly Harmless” the plot is more sophisticated and there are still some elements typical of the series but there’s also a component of pessimism never seen before.

Don’t get me wrong, we’re talking about a series that started with the demolition of the Earth in a novel that contained the deconstruction of the human species, irrelevant in the universe and not so important even on its home planet. However, there was a demented and satirical tone so you could easily laugh at human misery. In “Mostly Harmless” instead you can note that the narrative tone is bleaker so the laughter become bitter.

In what is his final chapter in the “Hitchhiker’s Guide to the Galaxy” series, Douglas Adams doesn’t just give a conclusion to the story of some of its protagonists, on the contrary adds further elements. In particular, the parallel universes are an important basis of the novel’s plot.

In the first part of “Mostly Harmless”, we find out what would would happen if Tricia McMillan hadn’t traveled with Zaphod. There are two alternative versions of the character, because there’s also the Trillian we met in the previous novels so we can compare their lives several years after the key event that made them diverge. Both versions seem rather selfish and therefore not very pleasant.

In contrast, Fenchurch completely vanishes. This is the point that has left me most puzzled because “So Long, and Thanks for All the Fish” was mainly dedicated to the love story between her and Arthur Dent. The fact that in “Mostly Harmless” she doesn’t even appear and is only mentioned for her disappearance is like deleting the previous novel. It’s like Douglas Adams didn’t know how to continue the story between the two of them and decided to wipe out Fenchurch completely.

Poor Arthur falls into depression and attempts to rebuild his live. In the end, just like the other protagonists of “Mostly Harmless”, he has regrets because in the end none of them seems to have found their place in the universe. If part of the story already seemed quite depressing, the ending is even worse.

Inevitably, “Mostly Harmless” is quite controversial among the fans of the Guide, also because neither Marvin nor Zaphod are in it. I think it’s pretty good but honestly I preferred to have the philosophical elements wrapped in a narrative with a more lighthearted tone like in the rest of the series. However, if you’ve read the previous novels I think that it’s still worthwhile to conclude the trilogy in five parts.