David Tennant (Tenth Doctor)
Billie Piper (Rose Tyler)
Noel Clarke (Mickey Smith)
Camille Coduri – Jackie Tyler
Shaun Dingwall – Pete Tyler
Roger Lloyd-Pack – John Lumic
Andrew Hayden-Smith – Jake Simmonds
Colin Spaull – Mr Crane
Helen Griffin – Mrs. Moore
Duncan Duff – Newsreader
Paul Kasey – Cyber Controller
Nicholas Briggs – Cybermen (voice)
Directed by Graeme Harper
Written by Tom MacRae
Script editor Helen Raynor
Produced by Phil Collinson
Executive producer(s) Russell T Davies
Incidental music composer Murray Gold
Production code 2.6
Series Series 2
Length 2nd of 2-part story, 45 minutes
Originally broadcast 20 May 2006
The episode opens immediately after the events of "Rise of the Cybermen". The Cybermen have the Doctor, Rose, Mickey, and the Preachers surrounded. The Doctor uses the recharging power cell from the TARDIS to overload the Cybermen, disintegrating them. The group escapes with Pete Tyler, but Jackie is trapped inside and presumed dead. As they flee, Pete explains to the Preachers that he is "Gemini", the Preachers' secret source of information on Lumic. Pete had thought he was communicating with law enforcement but accidentally involved the Preachers instead. From his hovering zeppelin, John Lumic orders the Cybermen to activate the EarPod devices and use them to control the people of London and bring them in for conversion.
When they reach London, the group discovers Lumic's zeppelin moored near the power station and head towards it. Ricky is killed by the Cybermen while trying to scale a fence to meet Mickey. After inspecting the power station, the Doctor determines that they must destroy the EarPod transmitter located on the zeppelin. Mickey and Jake decide to board the zeppelin, Pete and Rose pose as humans being controlled by EarPods, and the Doctor and Mrs. Moore try to find their way to Lumic. Pete and Rose are captured by the Cybermen when a now-converted Jackie catches sight of them. Mrs. Moore is killed by a Cyberman, but the Doctor discovers that each unit contains an emotion inhibitor to prevent their human side from taking over. He deduces that if he disables the signal from the inhibitors, the realisation of what they have become will kill the converted Cybermen. The Doctor is captured by a Cyberman and taken to see Lumic.
In Lumic's office, the Doctor discovers the Cybermen have captured Pete and Rose and have forcibly converted Lumic into the Cyber Controller. Mickey and Jake successfully disable the transmitter from the zeppelin by taunting a Cyberman into destroying the transmitter's power source. On the factory floor, the humans yet to be converted are snapped out of their trance. Initially confused, after seeing the cyber-conversion machines above them they quickly put two and two together and flee the factory in terror. The Doctor attempts to reason with Lumic to stop the conversions, but Lumic states that the Cybermen will simply take humanity by force. The Doctor, via the surveillance camera in Lumic's office, subtly communicates with Mickey on the zeppelin to find the inhibitor code. Mickey locates the code in the computer and sends it to Rose's phone. The Doctor plugs the phone into the computer systems, causing the inhibitor signal to drop and sending the army of Cybermen into despair. The conversion facility begins to go up in flames, and the group escapes to the zeppelin leaving Lumic to die. At the zeppelin they realise that Lumic is following behind them and Pete uses the Doctor's sonic screwdriver to sever the ladder, causing Lumic to plunge to his death in the exploding factory.
The Doctor, Rose, and Mickey return with Jake and Pete to the dead TARDIS. The Doctor plugs in the recharged power cell and revives the TARDIS. Rose reveals to Pete that she is his daughter from the parallel universe. Overwhelmed, Pete refuses Rose's offer to board the TARDIS and walks away, causing her to cry. Mickey, feeling that Rose no longer needs him, decides to stay in the parallel universe to help care for Ricky's elderly grandmother and to help the Preachers stop the remaining Cybermen, with Mickey ending his relationship with Rose. After the TARDIS dematerialises, Mickey and Jake plan to destroy a Cybus Industries factory in Paris.