The Daleks follow the TARDIS to the jungle world of Mechanus, infested with lethal plants. There, the Daleks release a robot double of the Doctor that is programmed to kill.
Robin helps an antiquarian excavate an ancient Roman treasure.
The merry men befriend an escaped Saracen prisoner.
The sheriff conducts a fraudulent lottery to raise money for Prince John.
A Jewish refugee asks Robin to help his friends escape persecution from an unscrupulous man called Malbete.