For the last 15 years, the mystery surrounding William has haunted "The X-Files", Scully and Mulder... and the fandom. Hundreds of theories have spawned, many plagued with questions that we are excited to ask... and maybe a little scared too.
So... Who is he? We might just find out this Wednesday in an episode written and directed by James Wong.
"A pair of teenage girls attack one another, each believing the other to be a monster, Mulder (David Duchovny) and Scully (Gillian Anderson) find that their investigation could possibly lead back to their long-lost son, William."
“Ghouli” airs this Wednesday, Jan. 31 (8:00-9:00 PM ET/PT), on FOX. Watch this behind the scenes video on the mystery of William, and check out the screen caps below. Spoilers ahead.