The winter finale of “Shadowhunters” is almost upon us and Valentine’s (Alan Van Sprang) attack on the Institute is imminent. To make matters worse, he’s also kidnapped Simon (Alberto Rosende). With all our heroes scattered across the city, it’s going to be a struggle to hatch a plan to take Valentine down while the clock is ticking.

Screener spoke to Matthew Daddario, who plays Alec Lightwood, about the winter finale — and how Alec will play into Valentine’s attack on the Institute.

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“In [episode] 10, we’ve got to wrap some things up,” Daddario says. “The Downworld is coming together, and we’re going to fight this Valentine threat — but at the Institute a lot of things are going to go wrong.”

One of these things going wrong involved Alec and Aldertree (Nick Sagar) being inside the Institute when Valentine strikes… The last place you want to be when a super-villain strikes is directly in his warpath.

“Alec is definitely going to have to deal with Aldertree — but maybe they’ll be friends, maybe they’ll see past each others’ differences,” Daddario teases.

Aldertree may not be anyone’s favorite person right now, but he and Alec will be forced to work together to take Valentine down from the inside while the Downworlder forces rally outside the gates.

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To be honest, Aldertree is probably the last ally we’d choose for Alec in a mission this important, but unfortunately, our first choice is a little preoccupied with his vampire venom addiction right now. Izzy (Emeraude Toubia) and Raphael’s (David Castro) burgeoning relationship is fraught with complications already, and that’s going to come to a head in the winter finale.

Now, thanks to her recent blowout with Alec, she might not arrive in time to save the Institute.

“Alec did something a little stupid,” Daddario says. “He didn’t realize what was going on with his sister because he was preoccupied with other things — which is embarrassing because honestly, he should be aware of what’s going on with his sister … We’re going to have to see if she gets better about this yin fen situation or if she spirals back out of control.”

“Shadowhunters” airs Mondays at 8 p.m. ET/PT on Freeform.

Posted by:Lindsay MacDonald

Lindsay MacDonald is a Los Angeles based entertainment reporter with an affinity for CW superheroes. She graduated from Pepperdine University with a major in Media Studies and a borderline unhealthy obsession with TV in 2012. She would much rather spend the day binge-watching ‘The Flash’ or sorting ‘Game of Thrones’ characters into Hogwarts houses than venturing outdoors. TV words to live by: “Never ignore coincidence. Unless, of course, you’re busy. In which case, always ignore coincidence.”