Fringe is new tonight (Fox, 9/8c) — and new every Friday from here on, straight through to the May 11 finale. And as with any home stretch of the series, lips are getting tight as to what’s to come (especially as regards the annually out-there Episode 19, which this year features Lost‘s Henry Ian Cusick, a “Young Olivia” and an “Old Nina”).

Here’s what the cast and EP Jeff Pinkner shared with us at WonderCon — including the latest word on the season and series finale plans.

THE ELITE EIGHT | That Fox elected to schedule Fringe‘s final Season 4 flourish with eight straight original episodes gets a big thumbs up from Nina Sharp’s good hand. “I’m so glad they’re showing them together,” says Blair Brown, “because they’re very powerful how they build on each other — not only bringing in characters that have been around before, even from the first season, but also characters coming in.” Through that combination of tales and faces familiar and new, “some stories will explain a little more than we knew before, some not,” says Brown. “Relationships deepen [or] have new tangents.”

‘MEANA’ | Speaking of Brown, the actress clarified that the “Mean Nina” who is in cahoots with David Robert Jones and tried to dupe Olivia a few weeks back is not a shapeshifter. Rather, “It’s a version of Nina that was thwarted, because there was no [William] Bell, no [sane Walter] Bishop, in that timeline. So you have a person with the same ability, who’s been left outside the circle — and Jones brings her in.” The way Brown teases, Meana’s worst may be yet to come. “This is not a happy person; this is a desperate person,” she warns. “She needs to be watched.”

HOME, SWEET HOME? | Pinkner says that the question of when or whether Peter will ever return to or restore his original timeline “won’t be relevant anymore very soon” — and Joshua Jackson himself reiterated as much. “Peter’s been a bit waffle-y lately. It’s him, it’s [Olivia], it’s not her…. I’ve gotta go home, I’m staying, I’m going to solve this universe, too. He’s just gotta make up his mind,” he told us. “[And] it’s answered in this next episode.”

THE 19th HOLY MOLY! | Ever since Henry Ian Cusick and Aussie blonde Georgina Haig were cast as FBI agents — the latter of which has been ID’d in paparazzi pics as “Young Olivia” (!), and accompanied by an “Old Nina” (!!) — there has been much head-scratching over what this season’s 19th episode will be about. (After all, previous Episode 19s have taken animated or musical detours.) Here’s what we know: As previously shared, Joshua Jackson — “for reasons I can’t tell you” — says he has scenes with neither guest star. Brown, meanwhile, seemingly confirms that pap pic caption, saying, “There’s another Nina coming up…. A time jump has happened.” You can also expect John Noble to offer another take (or two!) on Walter. “I think I’ve just done my 11th version of Walter,” he told us. “I did two new ones in Episode 19.” And… that’s pretty much all we’ve got. Oh, wait — maybe Seth Gabel is willing to part with some intel? “I can’t talk about Episode 19,” he deferred. “Just know that it’s really awesome and Desmond from Lost is in it!”

GRAND FINALE(S) | Ah yes, the annual renewal question. Pinkner, as of last weekend, had not gotten word either way, but said, “We’re feeling very bullish [and] positive that we will be coming back next year.” Which is nice, since he also reiterated that he and J.H. Wyman had no plans to rework the Season 4 finale into a series finale. “When we set out to shape this season, we started with the finale and knew that it wouldn’t change whether it was the series finale or season finale,” he said. After all, in an ideal world, the Fringe bosses have a very distinct conclusion to the series in mind. And when that day comes, Pinkner says, “It will feel very satisfying, it’ll be true to what the show’s been about, it will be true to the characters, and it will, hopefully, reward people who’ve invested in the show and stuck with it.”