Q&A: Name that monster movie – modern?

Question by : Name that monster movie – modern?
Saw another snippet of a movie and hope someone can ID it for me.

It started out with some people in a cave, looking at some kind of vague creature, talking about finding its weakness. “Everything has a weakness.”

Then it cut to a guy in scuba gear swimming. Next time I looked, the guy (I thnk it was the same one) was walking through a cave when a monster came after him. It had a crusty, dragon-like head and heavy, toothy jaws.

There were a couple of weird noises, and the monster took off. A woman came out carrying a funky-looking-pistol, and said it made sonic waves, and would repel the creature for a little while. She asked about Briggs (?) and the others, and the scuba guy said they didn’t make it. But he looked like he was lying. They may also have mentioned someone named Jack.

Any ideas? The monster was CGI, I believe, and it looked relatively modern.
Looks like you nailed it, A J! I will give you Best Answer when the option comes up–thanks!

Best answer:

Answer by Arena Junkie
The Cave.

http://www.imdb.com/title/tt0402901/

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