Torchwood "sting", from the original theme is still audible in numerous scenes). Although each episode of "Miracle Day" has a published individual title, "Torchwood: Miracle Day" is the only on-screen title used. The series is set in Cardiff, Wales and follows a rogue covert agency called Torchwood which investigates extraterrestrial incidents on Earth and scavenges alien technology for its own use. This Torchwood, led by Captain Jack Harkness, is a small, independent organisation, but began as the Cardiff branch of the larger Torchwood Institute, then-defunct, which began in the Victorian era. (Its origins were outlined in the "Doctor Who" episode "Tooth
Torchwood England's capital city of London, its membership declining and the organisation thoroughly broken over the course of the serial. Series four starts with Torchwood fully disbanded. Jack has left Earth after the events of series three, and Gwen has retired to be with her family. The group is then unofficially reformed, this time operating primarily in the United States, joined by two fugitive CIA agents who have been framed for treason. Unlike its parent programme, "Torchwood" centres on a team instead of a single character with companions. The show initially depicts a small team of alien-hunters known as Torchwood Three,