Corrected entry: After Gandalf saves the dwarves from the Goblin King they flee across several bridges, at one point leading them to a platform they use to swing across the a chasm. Initially Balin is seen at the front of the dwarves behind Gandalf, in the next shot he is standing at the back.
TwistedHaze36
15th Jan 2013
Correction: He actually waits for all of them to cross the platform so that he can destroy it - that's why he is then at the back of the group.