'X-Files' Reveals Series-Changing Twist Behind Scully and Mulder's Son

William, the long-hidden son of Scully and Mulder, was one of the most talked-about parts of The X-Files last season. This time around, he's playing a vital role once again, but there is a massive change coming for the character.

At the end of the Season 11 premiere on Wednesday night, it was revealed that an extraordinary, albeit frustrating secret surrounds William, and it's one that could change The X-Files forever.

WARNING: There are major spoilers ahead for the Season 11 premiere of The X-Files!

When the Smoking Man was trying to convince Skinner to join his cause, he was forced to tell the agent exactly why William meant so much to him. In one of the most shocking reveals in the history of the series, the Smoking Man said that he was actually William's father. Not only that, but the young boy was actually designed using alien DNA, in an effort to create the world's first superhuman.

In a series of flashbacks, the Smoking Man told skinner about his history with Scully, and footage showed the moment when Scully believed she was drugged by the villain. According to the Smoking Man, this is when he began the process of impregnating Scully with alien DNA.

This helps explain how William is projecting the horrifying visions of the future on Scully, seeing as how he's part alien.

Unfortunately, if you're a fan of Mulder and Scully, this means that their child isn't exactly theirs. Will Mulder still be able to love William like he's his own?

All will be revealed as The X-Files continues. New episodes air on Wednesday nights at 8pm ET on FOX.