There are numerous other allusions to Shakespeare's plays. Just before the Doctor steps out of the TARDIS, he exclaims "Brave new world", from Act V Scene I of "The Tempest". In an early scene a sign is glimpsed for an inn named "The Elephant". This is the name of an inn recommended in "Twelfth Night". The three Carrionites allude to the Weird Sisters from "Macbeth" (which was written several years after the setting of this episode); like them, the Carrionites use trochaic tetrameter and rhyming couplets to cast spells. When regressing the architect in Bedlam, The Doctor uses the phrase "A Winter's Tale", whilst the architect himself uses the phrase "poor Tom" in the same way as the 'mad' Edgar in "King Lear".