Harry proceeded through deserted corridors, though he had to step hastily behind a statue when professor Trelawny appeared around a corner, muttering to herself as she shuffled a pack of dirty-looking playing cards, reading them as she walked.

“Two of spades: conflict,” she murmured, as she passed the place where Harry crouched, hidden.  “Seven of spades: an ill omen.  Ten of spades: violence.  Knave of spades: a dark young man, possibly troubled, one who dislikes the questioner —”

She stopped dead, right on the other side of Harry’s statue.

“Well, that can’t be right,” she said, annoyed, and Harry heard her reshuffling vigorously as she set off again, leaving nothing but a whiff of cooking sherry behind her.

Harry Potter and the Half-Blood Prince – J.K. Rowling