The following contains spoilers from this Tuesday’s episode of The Flash.

This week on The Flash, one West got walloped by a whopper, while every effort to manage the “portal” between worlds could not keep a very familiar face from setting foot on Earth One.

ONE MOTHER OF A TWIST | Starting with the more down-to-Earth(-One) drama at hand, Joe faced off with Francine, asking Iris’ believed-dead mother to leave town. But after a heart-to-heart with Barry, Joe instead decided to tell Iris the truth — the second time in as many seasons that he has rocked her world with a wild revelation.

“It was much easier for Joe to pretend that [Francine] died than explain why she was gone and why she wasn’t part of Iris’ life,” Jesse L. Martin shared during our visit to the Flash set this week.

Still, it’s a whole lot of truth for Iris to process — though luckily (?) she has had practice. “It’s interesting,” Candice Patton notes, “because that was such a big plot point last season, the lying between family members, between Barry, Iris and Joe. So to go into Season 2 and find out there’s another huge lie that’s being kept from Iris is a big deal.

“But you’ll that this season, Iris is coming around to the idea of understanding that her father, even when he’s lying, he has the best of intentions, and that’s to protect her,” the actress continues. “So while that’s very frustrating for Iris, I think she especially gets it with her mother,” whom she believed was dead but actually had left town battling a nasty drug problem.

“She’s a little more OK with that than not knowing that Barry is The Flash,’ Patton says with a laugh. “That’s something he should have told her! I think she could have handled that!”

But is Iris ready to welcome back Mom? “She doesn’t know if she wants to unbury a part [of her life] that she’s not familiar with,” Patton says. “She’s had this idea of her mother that Joe’s told her about, and to find that’s not what really happened, I don’t know if Iris is emotionally ready to go down that path. So of course, she talks to her best friend Barry, gets some advice on what the best thing to do is.”

As for why Francine made the very bold move to surface at this particular time, “I still don’t really know,” Martin hedges. “All I know is that initially, she really wants to see her daughter.”

WELL, WELL, WELLS…. | The episode’s other big reveal came in the very final moments, when Earth-Two’s Dr. Harrison Wells (played by Tom Cavanagh) arrived in our world, having traveled through the “stabilized” breach based out of S.T.A.R. Labs.

“Shock, confusion, fear” are just some of the emotions evoked by the arrival of this other Wells, says series lead Grant Gustin. Versus the S.T.A.R. Labs founder that Barry thought he knew, but as actually a time-traveler in disguise, “It’s not the same guy,” Gustin notes. “It’s the actual guy that Barry always idolized and looked up to, but from a different world.”

Because this Dr. Wells is the real McCoy, “Barry is wanting to trust him… and in a way is quicker to trust him than he was to trust Jay [Garrick],” Gustin says. Earth-Two’s resident genius is not without his flaws. “He’s less of a bad guy and more of a douche bag,” Gustin quips. Adds Cavanagh, “It wasn’t written that way, but that’s how I decided to do it — more brusque and arrogant…. [He] is a lot less about ‘togetherness.'” As such, Cavanagh expects “a lot of vitriol directed my way this season, and that’s fine.”

All told, “It’s a very interesting relationship,” Gustin previews. “We’re shooting [Episode] 9 now and the layers are still getting peeled back.”

Want more scoop on The Flash, or for any other show? Email insideline@tvline.com and your question may be answered via Matt’s Inside Line.