SPOILER: Talia cannot be saved. She does die. Just let the game run through then continue playing. Good luck with the rest of the game. It took me awhile to beat it but I did unlock everything.

mfarrukh453: stand infront of the suit. If you are in the correct position, the game will tell you to press the "A" button. (xbox 360 version)

After beating Ra's Agul, as I am returning through the sewers, I come run into Killer Croc. Croc won't fight because he "smells death" on Batman. After Croc dives under water, I CANNOT unlock the metal gates to continue. Can someone tell me how to advance past this location ??