Zadok Allen is a character in H. P. Lovecraft's The Shadow Over Innsmouth, one of the few remaining humans in Innsmouth. After relating the history of Innsmouth to traveller Robert Olmstead, he was captured and presumably sacrificed to the Deep Ones by the Esoteric Order of Dagon.
Expanded Mythos[]
In Robert M. Price's short story "The Transition of Zadok Allen" (1995), Allen is depicted as having in fact been taken below the waves and transformed into a Deep One, where he presumably still lives.
Allen also appeared as an important non-player character in Bethesda Softworks' Call of Cthulhu: Dark Corners of the Earth video game in 2005.