The Hekatompathia (1582), the first English sonnet sequence, surprises its readers with a cryptographic puzzle at a critical juncture in the text. The puzzle's instructions, enumerated in five points, promise that a message can be deciphered using a specific set of published cryptographic tables. This odd, indeed unique, interruption of a poetic text has long baffled critics. Some have dismissed the puzzle as esoterica; one critic argued that the...