It's Gwen's first day on the job, and it's not going very well. After accidentally releasing a mysterious gas from a comet that landed, a new type of alien is let loose on the streets - an alien that's addicted to sex. Torchwood must find the inhabited body, and prevent anymore deaths from the violent form of sex.

A Ianto themed episode

Ianto Jones hides a very big secret at Torchwood - his half-converted girlfriend from the Canary Wharf Battle - down in the basement. He is quick to hire a Japanese doctor who believes he can "cure" her. But things soon go wrong, and the Cyberwoman's destructive powers are released to the whole of Torchwood. Upgrading is compulsary.

Whilst investigating a group of unexplainable deaths in a village, the Torchwood team are separated. Discovering further, Jack, Gwen and Owen find a scared man, hiding from the thing responsible for the murders. But Tosh and Ianto go that one step extra, and locate the killer, who wants them as their next victims.

With the Rift having been opened, people and objects throughout time are falling through it, and being spread across the world. "The thing in the darkness" has finally come, and Jack realises that he is the only one who can save planet Earth from the destruction that "the son of the Beast" will cause.

Captain Jack returns, as the Torchwood team reunite to fight a rogue Time Agent. The mysterious Captain John Hart is determined to wreak havoc, and needs to find something hidden on Earth. But with Gwen's life in danger, and cluster bombs scattered across the city, whose side is Jack on?

Gwen finds the darker side of Torchwood when a teenager disappears, investigating why hundreds of people have vanished without a trace. Jack is obstructing attempts to find them, and the answer appears to lie in the Rift.

As the team are knocked unconscious we find out how Jack, Toshiko, Ianto and Owen were initiated into Torchwood.

Captain John Hart returns to wreak havoc upon Jack's world, who ends up getting captured. It is up to the Torchwood team to rescue him and save the city.