"torchwood" stars john barrowman as captain jack harkness, the leader of the cardiff torchwood institute. barrowman also played harkness in series 1, series 3 and series 4 of the current "doctor who" (2005). eve myles plays gwen cooper, a policewoman who joins the group. gareth david-lloyd stars as ianto jones, a person who helps out and is a love interest of jack. jack harkness, ianto jones, and gwen cooper are the central cast members. also, naoko mori plays scientist toshiko sato. burn gorman plays doctor owen harper.