Merlin finds it hard to recover from the serket's poison. Morgana and Morgause step up their plans for the invasion of Camelot whilst he is out of action. Morgause continues to manipulate Cenred, as he prepares to launch an attack on the citadel. Morgana receives a powerfully enchanted rowan staff from Morgause to help her in her magical treachery. King Uther is still not able to rule as he tries to recover from the enchantment. Arthur is left to defend the attack on the citadel. Merlin knows it is down to him to try and stop Morgana without revealing his own powers.