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.

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.