In the Fourth season finale a body is found murdered at "The Lab," a popular nightclub, and everyone is a suspect. In an unusual twist of storytelling, Brennan, Booth and the Jeffersonian team take on various roles outside their normal duties, including serving as the nightclub staff as well as local law enforcement.
But, as the other person said this was a dream, which was part of the comma that Booth was in. Right at the end, when he wakes up and says "who are you?" he is meant to be talking about which Bones are you, as in dream bones who is his wife, or real bones who is his work partner.
:D :D
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