 The special radio episode's plot focuses on the Large Hadron Collider's activation and the doomsday scenario some predicted it might incite, as well as the Torchwood team's mourning of Toshiko Sato (Naoko Mori) and Owen's recent deaths in the "Torchwood" second series finale.Martha made her Big Finish Productions debut in the "Torchwood" audio drama "Dissected", released in February 2020.The introduction of Martha as the next companion after Billie Piper's Rose Tyler was announced by the BBC in a 5 July 2006 press release.