Two hundred gowns were made specifically for the series. Some were so heavily padded that Glenda Jackson could barely bend her arms. Some were so heavy that she could only wear them while sitting. Some required weights to maintain their shape. Some were so large that Jackson found it hard to walk through doorways.
Ronlad Hines (Lord Burghley) entered his dressing room and found a human head floating in the basin. He turned it over and found it was Vivian Pickles (Mary, Queen Of Scots). It was a false head for the execution scene. It was made of surgical plastic and a make-up technician was told to keep in water in a basin closer to the set. Ronald Hines dressing room basin was the closest.
Glenda Jackson would later reprise her role as Queen Elizabeth I in Mary, Queen of Scots (1971). Coincidentally, Rachel Kempson's daughter Vanessa Redgrave played the title character in that production.
In an interview published in Radio Times magazine to accompany the BBC's repeat showing of the series to mark its 50th anniversary in February 2021, Glenda Jackson recalled that the ornate ceilings on some of the sets were actually painted yogurt pots.