In Batman Begins, a young Bruce Wayne discovers that there is a huge cave under the Wayne Manor, by accidentally falling into it through a well. When falling, a colony of bats fly away. When Bruce decides to become a vigilante, and to bring fear in the heart of criminals, he naturally chooses his childhood fear as his symbol and costume.
I thought that it was just a clever idea of Christopher Nolan to introduce the background of the character. But (very mild spoiler for Batman V Superman)
in Batman V Superman, the short origin story of Batman has exactly the same scene.
Is this scene from the comics? Is it as iconic as the murder of Bruce's parents? (or, in another universe, as the death of someone's uncle Ben?)
PS: I am not sure the spoiler is really one. Better safe than sorry. I didn't include the batman-v-superman tag to avoid spoiler too.