At three 45 minute episodes, this was the longest serial to be transmitted during the 1980s and made it similar in length to the six-parters which had been common in the 1970s.
The last appearances of The Second Doctor and Jamie.
The story opens in black and white, with a scene featuring the Second Doctor and Jamie, which then gradually transitions to colour. This is a homage to The Second Doctor's era, which was shot in monochromatic format.
The location shoot in Seville kicked off production. When the wigs constructed for the guest characters such as Chessene and Dastari failed to arrive on time, the actors had to be fitted for new wigs in Seville. These Spanish wigs were subsequently used for the studio shoot in England in order to keep continuity.
The story originally took place in New Orleans. The setting was changed to Spain when the expected funding for location filming in the United States fell through.