Plot hole: Riddick seals them in the cave and goes to the ship. They fill bottles with the glow worms while he starts preparing the ship. Caroline magically appears outside the cave and climbing over the ridge that is overlooking the "town." She runs to the ship and tells him that she promised "them" she would return with more light. 1. How did she get out? If it was a second hole then the creatures would have gotten in 2. She never said she'd be back with more light to them.
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