Gwen: I know how devoted Merlin is to Arthur. He would never leave him at a time like this, not for a mere errand. Not unless there was something else. Something he doesn't feel able to talk about.
Gaius: My lady, there is something else. Something of the very greatest importance. And I dearly wish I could tell you what it is but I cannot, for reasons that affect us all.
Gwen: Then there is nothing more to be said, except for whatever it is, I wish him luck.