Season One of Gotham concluded with Bruce Wayne and Alfred discovering a secret entrance to what we're all assuming is a cave beneath Wayne Manor (who knows, perhaps the show will disappoint us all and it will just be a wine cellar). Having Bruce's father be responsible for that secret entrance and some sort of hidden base beneath the family home is a big departure from the comics, but one which makes sense given how difficult it would have been for the series to introduce these elements through the future Batman. However, it may be too soon to be delving into this type of thing. Even if this version of Bruce becomes a vigilante as a teen, we're still a good three or four seasons away from David Mazouz being able to convincingly portray that. He looks younger than his 14 years and certainly nowhere near big enough at this point to be out in Gotham fighting crime. Simply put, it wouldn't hurt Gotham to slow down a little when it comes to Bruce's evolution into Batman. His story arc in Season One was handled well and it was fun to see him toughen up and start becoming the good honest man from the comics who is intent of ridding Wayne Enterprises of corruption. Gotham isn't supposed to be Kid Batman though, and while teasing the Dark Knight is a good way to keep viewers hooked, it needs to be a slow build. The fact that the cave is being introduced so soon means that a big part of the Batman mythos has already been thrown into Gotham; is Bruce going to start building the Batmobile next? While watching his transformation into the city's Caped Crusader is a major draw, Gotham might be wise not to give away too much too soon.
