Glover has a marvellous Shakespearian script by David Whitaker to work with, some of it apparently in iambic pentameter. There are also fine performances by Jean Marsh as Richard's sister Joanna and Bernard Kay as Saladin. The Shakespearian nature of the whole production is emphasized by the way that the Arab characters are played by blacked-up English actors, something that would not be acceptable these days.
What this story demonstrates is one of the qualities that kept Doctor Who going through the 1960s and 1970s. No-one involved felt embarrassed about being involved in a children's show that was then only in its second year. Instead, they all treated it as if it was any other BBC costume drama, and applied the same standards. It was when people forgot this and started not to treat the whole thing seriously that the rot set in for Doctor Who.