On October 13, 1973, A group of government agents made contact with a group of Greys and the Cigarette Smoking Man offered up his wife, Cassandra, to the aliens in return for an alien fetus (TXF: "One Son").
The X-Files Movie was released to video on October 13, 1999.It is the name of Chris Carter's production company: Ten Thirteen Productions.October 13 and the number 1013 both occur frequently in the X-Files universe, as well as in other aspects of The X-Files (such as release dates). October 13 is the birthday of X-Files creator Chris Carter.