Review of both episodes:
A two part story quite reminiscent of The Time Meddler and other pseudo-historical stories where the Doctor finds events in the past being impacted by some interfering influence. This is nowhere near as good as The Time Meddler but it an OK effort. The TARDIS arrives in medieval England at the time of King John just before he is due to sign the Magna Carta in 1215.
I really like historical stories when done well and while this is certainly not done well enough to approach the best historicals the show has produced I do not think it is anywhere near as poor as its reputation. It has some really nice historical atmosphere, decent settings and costumes. It is solidly acted by the whole cast. It also benefits from brevity with a neat 2 part story rather than being dragged out. The only problem is that it is a bit lacklustre at times in terms of a plot that is not fully worked out and a couple of slow sections which seem fairly pointless. It has a decent showing for the Doctor's nemesis The Master who again - unsurprisingly - turns out to be the one playing havoc. His plot to use an android who can make himself look and sound like anyone in order to meddle in history and control worlds is perfectly good but it is not clear why intervening in the signing of the Magna Carta would be a worthwhile part of his plans. On the plus side he has an enjoyable sword fight which harks back to the Pertwee/Delgado days and it is a new twist on the alien in disguise motif with Kamelion and the overall plot to use this to gain power. There is some fun and some quality but it just does not rise above the level of a decent filler between more major stories.
My ratings: Parts 1 & 2 - 7/10.