Gaius has to remind himself that this isn't Uther anymore, this isn't his master and friend whom he has advised and supported over the years. No, that Uther is dead. Or rather: undead, and it is up to Gaius to stop him.

Still, he cannot stop himself saying, "Forgive me, my lord," in a tight and quiet voice before lopping the zombie's head off with his sword.

He steps over the body and rushes out the door. He will not linger. When zombies attack you cannot be idle, and Gaius has learned this lesson the hard way.