Warning bell

The warning bell is a warning system for the Citadel of Camelot. It sounded whenever a disturbance or incursion occurs (e.g. when a sorcerer is discovered, when a prisoner escapes, or in the face of a full-on attack on Camelot). Basically, when you hear Camelot's warning bells, you know some serious stuff is going down.

Series 4

 * The Wicked Day: When Dragoon the Great ran away after Arthur believed he had killed Uther.