Nathan Fillion Records World War Z (PHOTO)

Now that the Castle hiatus is in full swing (boo!), Nathan Fillion has some time to devote to some of his other projects.

Among his Stana-less endeavours, Nathan had the privilege of recording a chapter for World War Z — Max Brooks’s post-apocalyptic horror novel about the zombie war.

On Friday, Nathan posted a picture to his WhoSay account and wrote, “Just recorded a chapter of WORLD WAR Z for Max Brooks' audio book! See how thrilled I am? Can you guess which chapter?”

Any guesses on which chapter Nathan had the pleasure of recording, Castle fans? Sound off below!