John Hart

Captain John Hart is a rogue Time Agent who came through the rift into Cardiff in early 2009. He was an old friend and lover of Jack Harkness. (TW: Kiss Kiss, Bang Bang)

Information
Captain John Hart is a rogue time agent of the now disbanded Time Agency and former partner of Jack Harkness, both professionally and sexually. He has been in rehab for drink, drugs, sex and even murder.

Captain John Hart appears through the the Rift and asks Jack Harkness for help in locating three radioactive cluster bombs, apparently scattered across Cardiff; Jack Harkness tells the team he can't be trusted but agrees to help him. True to Jack's word, Captain John is lying and seizes the containers, trying to kill Gwen using a paralyzing lip gloss, shooting Owen and pushing Jack off the top of a building, thinking he's dead. However the containers, which are supposed to contain the location of an Arcadian diamond hidden by the lover he murdered, instead contain an explosive which latches on the DNA signature of her killer. Superficially altering his DNA using that of the Torchwood crew, Jack and Owen are able to save Johns life before forcing him back through the Rift but not before he revealed he'd found Jack's brother Gray.

Harts travels through time apparently took him to several different eras and places, as evidenced by his apparel. His coat comes from the Napoleanic Wars, his boots are from 17th century Italy, and he wields a samurai sword from feudal Korea, along with pistols from the present day that he stores in gunbelts from the American Old West.