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 Cooper 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. (TW: Kiss Kiss, Bang Bang)
John fins Jack's younger brother Grey and Grey attaches his vortex minipulater to John's skin nd puts a bomb on it he then threatens to set off the bomb if John does not do what he says John then plants a bomb ina abondond warehouse then sends him a message saying he was going to rip his world apart, he then takes Jack back to 27AD andlets him meet Grey, he is then helps Grey bury Jackalive forcing Jack to sufficate and revive over and over agian forever he then throws a ring (Whichis really a tracking device in with Jack so he can find him, he lies to Grey and tells him it's jst sendimental value.(Jack is descoverd by a past Torchwood team who reconis ehim as there employe and after questioning him freeze him in the Hub) John is then set free by Grey but he dicdeds to come back to Torchwood and find Jack and save him, he recuses Jack using the tracking device(The ring) that he gave to Jack before he buried him. He was not shown leaving Torchwood so it could be possible that he has became an employe.
Items
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.