Lord Peter Wimsey and Bunter are, of course, the invention of Dorothy L. Sayers. I hope she will forgive the pale imitations that wander through these pages.

Illya Kuryakin is a character from a 1960s TV series, The Man from UNCLE.

I have taken some liberties with history and architecture. To the best of my knowledge, Christ's College does not possess Milton's duelling pistols (if, indeed, "the Lady of Christ's" ever owned such things), and although Lady Margaret Beaufort's oratory window does indeed look down on the Chapel, I am not at all sure that it would be possible to climb up through it. Alan Turing's papers were not stored in a cupboard in the Cavendish Laboratory after his death, and of course he did not know any of the entirely fictional characters with which this story is populated.