Pietro Pacciani (January 7, 1925 – February 22, 1998), was a farmer of Mercatale, San Casciano in Val di Pesa, suspected of being the infamous serial killer "The Monster of Florence" (Il mostro di Firenze). The case was one of the inspirations for a character in the novel Hannibal by Thomas Harris. The 2008 book The Monster of Florence by Douglas Preston casts serious doubts on the culpability of Pacciani as the Monster.