Your character should have serious beliefs that motivate him.
These beliefs are also the foundation for his life as he knows it. He thinks that because of these beliefs that 2+2 will always equal 4. He’s so convinced of these beliefs that he is willing to do something big for them. He may go on an adventure. He may join a group of people who share these beliefs. He may make a major change in his life for the sake of these beliefs.
But what if these beliefs are false? What if underneath them is a foundation of deceit or corruption? What if what he thought was trustworthy, turns out to be a house of cards? Conflicts like this make for great stories. How can you create beliefs that can set your protagonist up for a devastating disillusionment?
In the beginning of the book, your character should be completely convinced that everything about their life is true, good and healthy. This is the status quo and at this point, there is no need to make any changes. But something happens, the inciting incident, somewhere in the first three chapters, that sets your main character on a journey, voluntary or not, that will test these beliefs over and over again. A really good story will have a big reveal – -AHA! This is the reality of the situation — come at a time when the main character and the reader won’t expect it. Then the fall out begins and your reader will be intrigued, wanting to know what your poor disillusioned main character will do now.
You can have him find holes in his personal history. Some families have that deep dark secret that no one is supposed to ever know. Like that the littlest brother is not really a sibling, he’s your oldest sister’s kid she had when she was fifteen. Or maybe Dad didn’t really spend time in the army, maybe he was in prison. Or maybe your favorite uncle is a drug dealer. This type of information can shake any main character. Can you come up with some beliefs for your main character that can rock his world?
You can have him find holes in his culture. There are inconsistencies that can’t be explained. There could be lies and propaganda that has been told to the citizens for generations that turn out to be false. There could be implications — our main character may have to turn his back on his childhood faith or upbringing to pursue truth.
You can have him find holes in his safety. Our lives are full of relationships that we trust and we take for granted. Is our public water really pure or is it laced with arsenic? Is our government really aware of our browsing history? Is the nice lady who invited you to her Tupperware party have plans to lock you in her basement?
You may have him find holes in his reality. Now this one is frequent in psychological thrillers. Our protagonist has been told over and over that he can’t trust what he sees. His mind could be messed with in such a way that he believes whatever he is told. His mind has been abused and he’s now a puppet of malevolent forces. This is fun to read but tough to write about.
You may have him find holes in his emotions. It could be that what he thinks are his motives for something — he wants to go to Private College even though his girlfriend is going to State University. What he doesn’t realize is that he really wants to break up with his girlfriend. He can’t articulate that, but it is the truth. Once he sees it, he’ll have to make a choice on what to do.
This is the purpose of having your characters believe things that aren’t quite true. The plot can hinge on what happens when they find out. Almost without fail, about halfway through the book, they’ll make a decision: do they keep going as if they don’t know the truth or do they choose another path? Regardless of what they choose there is going to a consequence, maybe even violence. They’ll have to make choice after choice, to stay safe or to risk their lives, to please others or please themselves.
This is what makes a rich and interesting main character.