For a show about experiences that can’t be quantified, The X-Files isn’t lacking numbers: 208 (episodes), two (movies), one (Speedo). But the most significant might be 10 — as in, the 10 new episodes now filming in Vancouver. After ratings for 2016’s six-episode revival soared to UFO-worthy heights, the sci-fi drama will return in early 2018, reuniting David Duchovny’s believer and Gillian Anderson’s skeptic for another run of out-there cases. Along with a first look at the new episodes, series creator Chris Carter gave EW classified intel on what to expect from the 11th season.

Mulder and Scully are swapping places

Viewers last saw Scully, immune to the alien virus sweeping the planet, on a gridlocked bridge trying to cure Mulder before it was too late. So what’s with this photo of Scully in the hospital — and Mulder looking healthy as ever? “Obviously something unexpected has happened,” Carter says wryly. But the showrunner promises he planned this reversal long before crafting that cliff-hanger: “Everything is by design.”

In Carter’s own words: “Shippers were heard”

After getting the professional side of their relationship back on track in season 10, Mulder and Scully will be drawn even closer together this year. Carter says fans rooting for the formerly estranged duo to fully patch things up “have something to look forward to.” But the partners are in for an intense journey; the pain of Scully’s decision to give up William (the son she shares with Mulder) for adoption 15 years ago still hangs over both agents. “William has been an absent center,” Carter says. “He will come to the fore.”

It’s not all heavy (but some of it is)

With more monster-of-the-week episodes this season (eight, in all), fans can expect season 11 to be united in theme but varied in tone. After episode one delves into the Cigarette Smoking Man’s (William B. Davis) backstory and apparent family ties to Mulder, the second hour opens with a time jump to put distance between Mulder and Scully and the events of the premiere. And episode three is a darkly comedic hour, penned by Carter, focusing on doubles and doppelgängers. But beyond the humor, the larger mythology of The X-Files — like the fallout from Scully’s abduction and the chip that was implanted in her neck — continues to shape Mulder and Scully’s world.

The conspiracy is getting crowded

A powerful figure played by Barbara Hershey emerges in this season’s story, though the showrunner says any resemblance between her red hair and Scully’s is purely coincidental. “It was a thrill to work with her,” Carter says. He also teases the addition of a so-called Mr. Y — and some characters who only appear to be new. Season 11 will also explore the motive behind one of the biggest shockers of last season: loyal ally Agent Reyes (Annabeth Gish) confessing that she’s in league with the Cigarette Smoking Man. And the showrunner says we’ll get a new angle on Mulder and Scully’s long-suffering boss, Assistant Director Skinner (Mitch Pileggi). “Familiar alliances are rattled,” Carter says.

After all this time, Mulder and Scully can still trust no one.