There ain’t no drama like family drama, and Cisco (Carlos Valdes) is about to learn that the hard way on The Flash.

Things between Cisco and his older brother Dante (Nicholas Gonzalez) have been more than a little icy since their run-in with Captain Cold (Wenthworth Miller) last season, and when the DC Comics villain Rupture comes to Earth-1 hell bent on revenge for Reverb’s (Valdes) death back on Earth-2, things aren’t going to get any better for the Ramon brothers.

“Rupture is a badass who wields this super threatening mask and ridiculous scythe that pretty much tears through everything and makes things explode,” Valdes tells Nerdist. “He’s a pretty formidable villain. The problem is, he reveals himself to Cisco and Dante, and when he takes off his mask, it’s Dante[‘s doppelgänger] from Earth-2. All at once, Cisco is having to grapple with the reality of choosing whether he should tell Dante about all the stuff that he knows about Earth-2’s existence.”

And remember that letter Cisco wrote to his family before he went to Earth-2, only to be delivered if he didn’t make it back?

“He wrote a letter to his mother and his brother, and that letter is going to play a pretty pivotal role in Cisco and Dante’s story in this episode,” Valdes reveals. “That’s going to come back into play in a pretty big way. And the reveal that Rupture is Dante’s doppelgänger is going to further test the relationship between Cisco and Dante, a relationship that is already very unbalanced. There’s just so much miscommunication there. Cisco wants to be a good brother to Dante but the fact of the matter is, they just do not vibe at all, pardon the pun.”

Going into this episode, the status of Cisco and Dante’s relationship is … well, not so great, to put it lightly.

“The last thing that happened between them was a pretty traumatic event, when Captain Cold essentially threatened Cisco that he was going to kill Dante if he didn’t reveal Barry’s [Grant Gustin] secret identity,” Valdes says. “In order to save his brother, since his family is incredibly important to him, Cisco compromised Barry’s identity. He betrayed Barry for Dante. You would think that that trauma between the two would have brought Cisco and Dante closer together, and actually there was this whole lovey dovey scene that was cut from the very end of that episode. So that ended up being a blessing in disguise because in this episode, that disconnect between the two brothers is still there. There wasn’t a resolution between them anymore. We’ll find them like that in this episode and it makes it that much more emotionally charged. After all this time, all this resentment from what happened with Captain Cold is still there.”

Valdes reveals that Rupture has been told by Zoom (Teddy Sears) that Cisco was actually the one to kill Reverb, even though it was Zoom who delivered the killing blow.

“Rupture and Reverb were brothers on Earth-2, so it’s an Inigo Montoya situation, from Princess Bride,” Valdes says. “I killed his brother and so when he comes to Earth-1, he’s coming after me. This is real, bloodthirsty vengeance.”

As if Cisco doesn’t have enough to worry about already, he’s also going to be swept up in Harry Wells’ (Tom Cavanagh) crazy plan to recreate the particle accelerator explosion to try to get Barry’s speed back.

“It is absolutely insane. You’ll find in this episode when we start getting into the logistics and the science of how exactly we’ll recreate the explosion, it’s absolutely an insane idea,” Valdes says with a laugh. “Cisco has reservations about it. But the fact of the matter is, what other option does the team have? Barry needs his speed to save Caitlin [Danielle Panabaker] from Zoom. There’s no way to save the day without gaining back that speed. It’s one of those ideas that, at the end of the day, if you really think about it, it’s so crazy that it just might work. You know what I mean? It’s just a matter of the team being backed into a corner. There’s no way to fix the situation other than to try this insane idea. Cisco feels okay putting his trust in Harry because he knows Harry’s very smart and underneath that curmudgeonly façade, there is a very smart and compassionate man who’s only looking to do the right thing.”

Expect the debate over whether or not they should listen to Harry’s idea to split the STAR Labs team.

“It’s going to be a very difficult conclusion to come to,” Valdes says. “There are going to be parties within the team who want different things. There’s going to be an addition to the team. The dynamics are going to change and be tested, absolutely, as they try to figure out if they should do this idea or not. But this is really the only chance they have. It’s ultimately up to Barry since he’s the leader of the team and it’s his decision to make. And he’s always willing to sacrifice himself for the good of others so that informs his decision.”

As The Flash ramps up towards the season finale, Valdes is most excited for fans to see how “the last few episodes get really, really huge.”

“That’s kind of our thing now, to blow things up in the end,” Valdes says with a laugh. “What I love about our show is that the science behind it gets into this kind of mysticism that allows it all to be really unpredictable. It can go in any direction at any moment. So the team has to use the crazy logic of this sci-fi to defeat Zoom and it all leads to a huge spectacle in the finale. It all starts to funnel and spiral towards that one event and fans can expect to be constantly surprised and satisfied, and there might be a cliffhanger at the end. Who knows?”

The Flash airs Tuesdays at 8 p.m. on The CW.

Images: The CW