“It’s a trap!” ~ Admiral Ackbar
When you write a character without motivation, it can seem like you found an endless well of inspiration. Go left, go right, go back, go forward, but whatever you do, don’t explain.
But the risk you run is a frustrated and confused audience. The risk you run when writing such a character is that after a while you forget your original reasons for creating that character. Someone said—I may have quoted that person on this site in the past—that you must love your characters to bits. But a nihilistic character absorbs that love to the point of perfect osmosis, it passes straight through without giving the needed feedback to the love-giver.
I digress and it is time for some examples.
Most recently, I watched Matthew Mcconaughey in Interstellar. There is a scene that bothered me throughout the film, of him deciding to head into space and “save the world,” without really giving a second look at his daughter, which he leaves behind crying in her room. We witness his many adventures throughout the film, but we never understand what drives the character. He is as cold as the antagonist revealed later in the story.
In the book Leviathan Wakes (Book 1 in the Expanse series), we are introduced to a washed out detective Miller, who fits the very definition of nihilism. He loses some pretty important elements to his life (trying not to spoil it), but his emotions are non-existent, the only expression is movement of the character throughout the story. Which is fine, except that his choices also appear at random or at least as those of a very depressed person.
Exhibit 3 is Vanessa Ives in the TV Show Penny Dreadful (Amazon link), which I also previously expressed my admiration for on this site. What I liked about this show is the melding of different mythologies into a shared adventure. What nearly drove me out was Vanessa Ive’s descent into her own darkness, one entirely devoid of meaning. The character is haunted, ever since she was a child, by an image of her mother cheating and later invokes that pain onto her mother’s lover, by seducing his daughter Mina’s fiancé. That leads her to being possessed by some kind of devil and we witness the scenes of her combatting that demon.
The salvation to nihilism is some kind of overarching faith or goal. Interstellar’s goal is to save the world and for a father to rejoin his daughter. The driving engine for this is the protagonist’s thoughtless (nihilistic?) bravery. In Leviathan Wakes, Miller entire focus is on solving a case, which is what drags him out of the various messes he creates or is a part of. But we also see this drive to destruction, which is hard to digest. Vanessa Ive’s “engine” is her faith and the overal goal is save Mina, the woman whose life she destroyed at some point.
A character does not need to be loved and understood always, but he must have a meaning to his actions. Some of the examples above showcase that this meaning can be lacking and must be compensated over time. But it also risks to frustrate the audience throughout the story and absolutely must be paid off.