It was not originally intended as the finale of Season 12, which would have been the next story that aired after it in the following thirteenth season; that story was withheld to push forward the air date of Season 13. This was achieved by borrowing a story from Season 12 to reduce the number of stories that would have to be produced to fill the next season's agenda. It was further significant for being the first Doctor Who story released on home video, and inaugurated the franchise's VHS, Betamax, and Laserdisc ranges.