When authorities receive a telephone tip from someone named Sydney, the FBI and ATF stage a raid at Temple of the Seven Stars, a religious cult the anonymous caller says is abusing children and has a cache of firearms. Mulder feels that he's been there before and has a powerful sense of deja vu. They arrest the cult leader Vernon Ephesian and several of his followers including one of his wives, Melissa Rydell Ephesian. They don't find the arms cache however and Assistant Director Skinner thinks they have less than a day to get some hard evidence or they will all be released. Melissa seems to be suffering from multiple personality disorder and has a personality known as Sydney, the person who made the call. In fact she has several personalities including a Southern belle who tells Mulder they were there for a Civil War battle. Mulder thinks she's recounting a past life.
—garykmcd