To give a darn means to care about someone or something, and in this sentence the people who didn't care before suddenly become believers.
Context: So when it's the end of the world, kincaid was saying, people who didn't care about anything before suddenly become believers.
Hypothesis: So when it's the end of the world,kincaid was saying, people who didn't give a darn before suddenly become believers.

Is the hypothesis incorrect? (Yes, no, or unknown)?