"It came from House Lannister after you were made a [lord/lady]. It was hidden among some taxation ledgers. I suspect they didn't know they were sending it."
"I wish to read this book and see what secrets it holds. Find a way to open it."
"Very well. Find this key, Maester Lucas. I want to know what the Codex contains."
"The Golden Reliquary is a coffer of gold, and acts as both key and code-breaker for the book. I believe its hidden in Casterly Rock."
"What I want to know is how did it come to be in our possession?"
"How do we open this book? The steel lock is impossible to pick."
The maester enters, clearly overjoyed. "I've found reference to the book in a old diary, my [lord/lady]! It's called the Red Codex."
"It was written during the Andal arrival in Westeros. Its authors have been many over the years."
"Tell me of it. Who wrote it? Where did it come from?"
"Well, it has come to our hands. Therefore, we shall further investigate its secrets."