I need help finding some Batman/Bat-cave media

I saw a clip of what looked like to be a scene form one of the 2000s era animated shows, the scene was of Gotham police finding the bat-cave in the future, they use the records to defeat a villain, the records were a voiceover of batman recalling some old plans.

That’s all I remember, I could’ve just stumbled upon something fan made but if it’s a real scene I’d like some help looking for it