Torchwood is a British science fiction television series that serves as a spin-off to the long-running series Doctor Who. Set in Cardiff, the show follows the exploits of the Torchwood Institute, a secret, non-governmental organization tasked with investigating extraterrestrial incidents, capturing alien technology, and defending Earth from supernatural threats. Led by the enigmatic and immortal Captain Jack Harkness, the team operates from a hidden base known as the 'Hub' located beneath Roald Dahl Plass. Unlike its parent show, Torchwood is aimed at a more mature audience, exploring darker themes, complex moral dilemmas, and the personal lives of its team members. Throughout its run, the series shifts from episodic investigations of alien artifacts to high-stakes, serialized narratives that test the loyalty and survival of the team as they face existential threats to humanity.