A series of powerful events begin through the third season drama. The season opens with a series of adventures through the middle piece, a blue stone that appears to be of high value in the cover of Cornelius Sigan's coffin. From another perspective, Arthur tries to understand how his rivals can allow him to win as king, so he pretends to leave the court and enters the lists in disguise to win on the basis of real merit and sweep.
This was still run-of-the-mill Merlin, and proof that, so far at least, the writers aren't planning to deviate into exciting and fresh parts of Camelot anytime soon.
