Final Quest

The green dragon steps forward. "Sir Knight," he says politely. "Have you seen two pale stones anywhere around here?"
"If they are jewels, they would have been stolen," the knight answers, his vocie sombre. "Either that, or they are guarded by a horrible monster. There are many terrible creatures around."
The green dragon bows somehow. "Thank you," he says.
"Remember, it is easy to come here, but not so easy to get out again," the knight replies.
What do you do now?