Apparently, Monday night's episode, "Unearthed", was an un-aired episode from season 1. However, the press release for the episode suggests something different:
"While the girl's mind-bending condition intensifies, Walter dusts off some old lab bidyo and hypothesizes the unthinkable, sending Olivia and Peter to investigate the bewildering case in an original "Unearthed" episode of FRINGE and
here's another mystery: is it an unaired episode from Season One or is it from an alternate universe?"
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