The Doctor, perhaps because he missed his recently-departed granddaughter, asked Vicki to come with him and the others, making her the first companion that the Doctor was seen to willingly invite to travel in the TARDIS. Being invited to travel with him would later become an important hallmark of the Doctor's companions.
The sound the Sand Beast makes while dying was modelled after the "horrible noise" a dying Dalek made in "The Daleks".
Jacqueline Hill was injured during the scene where Barbara shoots Sandy. The explosive connected to the wooden gun went off with more force than expected. She suffered shock and a sore face.
This was the first episode to make the UK's top 10 most watched programs list.
This episode takes place on Dido in 2493.