Infinity Train
The Infinity Train was an otherworldly train whose cars contained their own environments, complete with Denizens who could not leave the Train. Humans from the normal world would be summoned into the Train and given a green number on their palm that counted down the amount of personal growth they had to go through before the Train would allow them to return home, with the cars intended to serve as enlightening trials, and the Denizens as guides.
One version of the Train was connected to a universe where Jenny Everywhere was a case worker. This universe's Train was sufficiently otherworldly to have its own Jenny, but although the Train Jenny did not have the ability to shift outside of the Train, she had access to the telepathic network and thus the two were aware of each other. This allowed Grace Monroe, who had begun to form a relationship with Jenny aboard the Train, to carry it on with her human counterpart after she had to return to her own world. (PROSE: Shippy Shifter Snippets)
Behind the scenes
The Infinity Train was the main setting of the series of the same name.
