Just when Angel, Spike, Illyria and Gunn think it's game over, there luck turns around. Well, sort of. The new Wolfram & Hart CEO agrees to make all of the demons encircling them go away. However, nothing comes without a catch.
The terms of his deal are that Spike signs a contract with him. The contract states that a new Hellmouth will be built underneath Wolfram & Hart. Only Spike's signature can create the Hellmouth as he destroyed the one in Sunnydale. The CEO threatened to kill Willow if Spike didn't sign, as he wanted to use Willow in a spell to exterminate all slayers. In order to save Willow and the slayer's lives, Spike signed, and therefore a new Hellmouth was opened.
With everyone telling her that she is needed in Los Angeles, Buffy decides to set up shop in Los Angeles to help with the problems of the new Hellmouth. With Giles' connections, they manage to acquire a hotel big enough to host the Slayers and the Watchers. Now they must deal with the problems of the Hellmouth, and the clashing of Buffy and Angel's teams.