"Just a few like-minded people trying to keep the modern world at bay."
REVIEW: Roadrunners may be Scully-centric, but I don't feel like it's a problem, even if we're at a point when we should be finding out more about Doggett. Fact is, in the few scenes he's allowed, we do. Doggett is, first and foremost, a cop. And we see that here. He gets the instant cooperation of other cops. He reacts to situations like a cop does. His go-to is police work and police action. He has a cop's instincts. He's impeccably professional too, and when Scully essentially ditches him and accepts a case without filling him in, he takes the emotion out of it. There's a single beat of silence and then he dispassionately does the required research. At the end, he doesn't say "I told you so"; he waits for Scully to admit her mistake and agrees with her. So while he's not in this as much as she is, it's still about their evolving relationship, and the trust she should be placing in him. And it shows us why this must always be a show about partners; it can't be about a single hero.
The monster of the week is also more successful than Patience's, a gross spine worm that, Trill-like, needs a human host to live and speak through. A small community of Luddites caters to it and worships it as the Second Coming of Christ, ever seeking a host body that won't fail in a few months to bring about its Glory. The cultists are all nice folks, so I do wish we'd had to chance to hear the parasite's teachings. It might have shed light on these people's faith. As is, they're not unsympathetic, but seem a little crazy. But the parasite is only allowed to be duplicitous as it tries to wrangle a doctor for its host, and no rhyme or reason is applied to the choice of host/sacrificial lamb, nor is Scripture used to explain their doctrine.
The cult's power is in numbers, and in its ability to cut a person off from modern conveniences such as phones and vehicles. As in Patience, Scully is irritable and paranoid, but her suspicions don't save her from the trap. And sleeping with her gun doesn't save her from being exposed to the parasite. They take it quite far, to the point where you think she's about to lose control of her mind; it's all very effective. The cult loses all our good will at that point, as Scully screams for the life of her unborn baby (Anderson also adds a nice touch much earlier when she touches her stomach while evaluating if she should take a long walk in desert terrain), and they nevertheless put their Messiah in her. And then they turn into a zombie horde, breaking windows to get at the fleeing FBI agents. So they can mope about Doggett literally shooting their religion down, but without knowing what that religion was really about, it's hard to care much for them.
REWATCHABILITY: Medium-High - A gross monster, a believable and non-exploitative Scully-in-danger scenario, and an efficient and illuminating use of Doggett. The cult's motives need filling out though.