WARNING: This article contains spoilers for this week's episode of The Gifted, "rX," which premiered tonight on Fox.

The disappearance of the X-Men and Magneto's Brotherhood, somehow connected to a 9/11-type tragedy, is on of the establishing mysteries of The Gifted, permitting the government's Sentinel Services to operate unchallenged and leaving the Mutant Underground to fill a void left by their absence. However, as we learned in this week's episode, those aren't the only mutant groups in the world of the new Fox drama.

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In the series premiere, parents Reed and Caitlin Strucker (Stephen Moyer and Amy Acker) are forced to become fugitives after their teenage children (Natalie Alyn Lind and Percy Hynes White) are revealed as mutants during a harrowing incident at a school dance. Pursued by Sentinel Services, the family seeks the help of the Mutant Underground, a national network that protects mutants and, when necessary, smuggles them out of the country.

Separated from his family, who escapes with the Mutant Underground, Reed is arrested, and in "rX" is interrogated by Sentinel Services Agent Jace Turner (Coby Bell), who seeks any leverage he can find to use against the (now surely former) federal prosecutor. Turner uses every tool at his disposal -- oh, all right, primarily legal threats against his family -- to force his cooperation, but Reed isn't one to be intimidated or manipulated; after all, he's used many of those same tactics, against mutants.

However, past all the talk of terrorism charges and co-conspirators (they even hauled in Reed's mother, played by guest star Sharon Gless), it's obvious Turner isn't all that interested in the Strucker family. No, his real target is the Mutant Underground.

The agent reveals he knows Reed used information contained in the police file of Lorna Dane (aka Polaris) to make contact with the underground network. And that's where the reference is made to another mutant group from Marvel Comics.

"You should know there's been talk for quite some time about classifying this organization as a terrorist group," Turner says, "like the Brotherhood or the Mutant Liberation Front."

Ah, yes, the Mutant Liberation Front. Introduced in 1990 in New Mutants #86, the MLF was a group of disaffected superpowered youths dedicated to committing acts of terror in the name of mutant rights. Originally ed by Stryfe, a clone of Cable, the team was positioned as a philosophical opposite of X-Force, and operated across the globe (although the exact size and scale of the group was never clear). The original incarnation included the pyrokinetic Rusty Collins, the super-strong Forearm, the force field-generating Skids, the super-size Sumo and the sadistic Wildside.

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On The Gifted, Reed protests that the Brotherhood and the MLF "are nothing like the Mutant Underground, but is dismissed by Turner, who points out that he was prosecuting Lorna Dane just three days earlier: "So, what, now she's a freedom fighter?"

It's of course too early to know whether the Mutant Liberation Front is simply a reference to further develop the setting of the series, or if the writers are subtly laying the groundwork for the group's introduction later in the season. The MLF would offer an intriguing counterpoint to the Mutant Underground, muddy the societal debate about mutants, and even offer stark choices to Lauren and Andy Strucker as they come to terms with both their emerging powers and their futures in a world that, in large part, hates and fears them.

Airing Mondays at 9 p.m. ET/PT on Fox, The Gifted stars Stephen Moyer as Reed Strucker, Amy Acker as Caitlin Strucker, Sean Teale as Marcos Diaz/Eclipse, Coby Bell as Jace Turner, Emma Dumont cast as Lorna Dane/Polaris, Jamie Chung as Blink/Clarice Fong and Blair Redford as John Proudstar/Thunderbird, Natalie Alyn Lind as Lauren Strucker and Percy Hynes White as Andy Strucker.