At about the age of 21, Charles Dodgson began a series of numbered diary volumes that he was to keep until his death. Volume 1 of this series was begun before October 1853 and the final volume, number 13, ended in December 1897, just a few weeks before his unexpected death from pneumonia. Although not especially revealing or personal, many of the entries detail a life much at odds with the mythic image of the shy, reclusive child-obsessed Carroll. They show him socialising with famous artists, writers, politicians and members of the royal family. They also show he was close to a number of adult women throughout his life, and was indeed the subject of gossip as a result. Perhaps most significantly, large portions of these diaries are now missing, presumed destroyed by Carroll's family after his death. The reasons for this censorship are currently unknown, though the evidence suggests it may have have been connected with his growing religious problems, and/or a possible unhappy love affair.

To add to the puzzle, the volumes for the early 1860s are filled with expressions of a psychological pain and a deep guilt that have never been explained. Altogether these strange, haunting and laconic documents present one of the great literary mysteries of our time.