A ghost appears in Jackie’s (Camille Coduri) flat, which she thinks is that of her father. The Doctor (David Tennant) and Rose (Billie Piper) are surprised. Jackie tells them that it’s happening everywhere on Earth and the people are used to it. The Doctor does determine that something is forcing its way into this universe. He tracks the signal and follows it with the TARDIS, with Rose and Jackie on board, ending up at the Torchwood Institute in Canary Wharf. The Doctor and Jackie are taken by soldiers to see the director Yvonne Hartman (Tracy-Ann Oberman). The TARDIS is impounded with Rose inside.
Yvonne shows the Doctor the invisible breach which is the source of the ghost energy, and a void ship, designed to travel the void between universes, which came through as well. The Canary Wharf Building was built around it to try to harness it as an energy source.
Rose, pretending to be a Torchwood employee, leaves the TARDIS and goes to the sphere chamber, where she finds Mickey (Noel Clarke), also pretending to be a Torchwood employee. It seems an advance guard of Cybermen have initiated an unscheduled ghost shift to open the breach, causing millions of ghosts to appear. They will eventually become Cybermen. Mickey tells her that in the alternate universe where he has chosen to live the Cybermen have disappeared. He has come through to stop them from invading this universe. Rose is horrified when the sphere opens, and four Daleks come through. To be continued.
A minor character was played by Freema Agyeman (Adeola). She impressed Russell T. Davies and was hired to play Adeola’s cousin Martha Jones, the next companion. They managed to keep the Daleks secret until the end. The episode was very well-received, called tense and full of drama, tears, and adversity. Murray Gold’s theme for Torchwood first appeared in this story.