Merlin - The Tears of Uther Pendragon Part 2

Merlin is rescued, but now that he knows Morgana's secret, she and her sister, Morgause, continue their plan to take over Camelot, while Uther is still not in his right mind.
The armies gather to put Camelot to siege and to attack.  The army scenes are very Lord Of The Rings in tone and excellent to see in a weekly television show.  Using magic, Morgana releases the armies of the dead to help in their fight for the throne.
This is a very interesting storyline where Merlin must be very careful not to accuse Morgana of treachery as Uther could have him killed without the proof required.  How does Merlin stop Morgana and her sister, restore Uther and save the kingdom, without revealing his own magic?
A great two parter to open the season!