Simon Pegg had great difficulty saying "the Mighty Jagrafess of the Holy Hadrojassic Maxarodenfoe". The scene in the episode features the best take he could do, with the monster growling over the bits he got wrong.
Bad Wolf Reference: On Satellite Five, the "Bad Wolf Channel" is broadcasting news that the Face of Boe is pregnant.
The "frozen vomit" that Adam spits out in one scene was in fact a "kiwi and orange ice cube".
The working title for this episode was The Companion Who Couldn't.
Simon Pegg had grown up with Doctor Who (1963) and considered it a "great honour" to guest star. He was pleased at being cast as a bad guy. Pegg had previously played Don Chaney in the Eighth Doctor audio play Invaders from Mars.