This episode sees a redesign of the TARDIS interior. Barry Letts was unhappy with the redesign. The set was damaged shortly after recording on this particular serial wrapped and, as a result, was discarded.
The Doctor's TARDIS materializes both inside and around the Master's TARDIS at the same time. A similar effect happened in Logoplis (1981) when the fourth Doctor materialized the TARDIS around a regular Police Box, and realized The Master had done the same thing.
This episode was watched by 7.6 million viewers on its original transmission.
This episode takes place in Atlantis in circa 1500 BC.