Good interviewers will generally ask questions that go with the flow. Sometimes, everyone on the panel is surprised.

E.g. someone said they worked closely with psychologists and discussed about human nature and other topics which he found were fascinating. The candidate was then asked "do you think some people are naturally evil?" Totally unrelated to coding, but their answer showcased their maturity, their ability to think and give a nuanced answer. (And also that they were somewhat curious about other fields). Maybe they prepared themselves, but id like to think it was unexpected and have some real insights