What are we looking at in this spoilery Dark Knight Rises set photo?

The Dark Knight Rises is currently filming in India, and a photographer snapped this set picture of a mysterious green pool.

It looks suspiciously like a Lazarus Pit, a stewing geological brew that Ra's al Ghul uses to heal his wounds and prolong his lifespan (Josh Pence is playing Ra's al Ghul in flashbacks). Then again, the Lazarus Pit seems a little too outlandish for Christopher Nolan's more grounded approach to the Batman franchise.

My guess? Nolan has now become so fantastically megalomanical that he demands daily ablutions in an abandoned quarry full of Ecto Cooler.

[Batmen of Cinema via Latino Review. Thanks omgwtflolbbqbye!]