Torchwood Four
From Tardis Wiki, the free Doctor Who reference
Torchwood 4 was a branch of the Torchwood Institute. The nature of this branch and its personnel were unknown. Jack Harkness stated it was lost. (TV: Everything Changes) Its location is unknown, but it was most likely located in Belfast as all the other Torchwood bases (with the exception of Torchwood India) were located within the capital cities in the United Kingdom. Agnes Havisham claimed that Torchwood Four's disappearance was a "messy business". (PROSE: Risk Assessment)
