Stephen and Vicki have discovered the Monk's secret, he has a TARDIS, and from the same world as the Doctor. The Doctor discovers the monk's plan, to lure the vikings in with fires, and destroy them. Whilst in the Monk's TARDIS, Stephen and Vicki learn the monk has been meddling with time, discussing powered flight with DaVinci and swindling banks. The villagers must stop the Vikings, and the Doctor must stop the Monk. The Doctor makes an enemy of the Monk.
I love the Monk's TARDIS chockablock with ornaments and antiques, that's exactly how mine would be! The Monk is irresponsible, but is he a totally bad guy? only time will tell.
Alethea Charlton is worth a mention for her performance as Edith, it's what I can only describe as charming. Such an authentic face. Great chemistry between her and Hartnell.
This has been a totally brilliant story, and Part 4 is even better. I love the concept of the Monk as a renegade Timelord, the original idea back in 1965, long before the Master, Rani, War Lord etc.
Gloriously written, this episode defies its years, and feels like a basis or vision for the show's future direction. Absolutely love it. 10/10
How cool are those closing credits too.