Shadowhunters Bosses Tease Consequences of Lillith's Mark on Clary

Shadowhunters is about to return for the second half of its third season, and not a moment too soon! That only took 9 months...

When we pick back up though, a lot less than 9 months will have passed -- more like a week or so -- and everyone will be dealing with Clary's (Katherine McNamara) apparent death and how to move forward without her. This final stretch of episodes leading up to the two-part series finale will have to tie up a lot of loose ends, take characters through break-ups and makeups and presumably deal with Clary's brother, Jonathan (Luke Baines), once and for all.

TV Guide talked with showrunners Todd Slavkin and Darren Swimmer about what to expect when Shadowhunters picks back up, as well as which characters we might see pop up again before all is said and done.

Now that Clary is presumed dead, who will be taking it hardest when we pick back up?
Darren Swimmer: I would say it's a tie between Jace (Dominic Sherwood) and Luke (Isaiah Mustafa), but they're handling it in completely different ways... With Jace, it's putting him into a deep depression and his guilt is almost something he can't bear. With Luke, it's driving him on this quest to figure out answers. He has this glimmer of hope that somehow could she survive that, as crazy as it sounds.

I'd assume Simon (Alberto Rosende) is probably not taking it great either, considering it was his mark that caused her death in first place?
Todd Slavkin: Yeah, he wants that thing off his forehead at any cost. He feels like he's the one that actually "pulled the trigger", so to speak. He will do anything. It's been such a pain in the butt this whole time, this mark of Cain, so that will really propel him forward this season.

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How much can we expect the Mark of Cain to play into this final stretch of episodes?
Slavkin: In a really, really big way, the desire to lose the Mark of Cain definitely creates a bond with Isabelle (Emeraude Toubia) and obviously that complicates things ahead. The Mark of Cain is just one of the things [Simon] does this season... But vampire politics play a big part of it and things get complicated. You haven't seen the last of Heidi, you know? Poor Simon has his hands full as we move forward and Alberto delivers in a huge way and we get to do things with him that we never thought this kid Simon would be able to do. It's really cool.

We do know Jonathan is back in the flesh this year, so will we see any changes in him this time around? Has the death taught him to be a better person?
Swimmer: Well, he sure won't have the face that he had, previously, because that was Sebastian Verlac's face.
Slavkin: I think he comes back in his pure form, but as we're going to learn through the season, his pure form isn't necessarily the wholesome good old boy. Jonathan Morgenstern has been through a lot in his life. We've learned a little bit about it when Sebastian kidnapped Valentine in Season 2 and was talking about how he was abused and all that. Well, that was the real Jonathan. That wasn't Will Tudor's Sebastian Verlac. This was this kid that you're going to meet in [Episode] 311, the true Jonathan Morgenstern. He's a very complicated guy who's dealt with emotional and physical abuse by both of his parents and that doesn't necessarily equal into a good person. He wants what we all want, which is love, acceptance, and family. Like any good villain, I think you understand what his motives are. He just has strange ways of achieving them.

Definitely. And since Clary is sort of his only family left, what can you say about is their dynamic in the second half of the season?
Swimmer: I can say that the bond of blood is something that's hard to separate. As much as Clary wants nothing to do with him, it's hard for her to actually achieve that separation. It's only going to get harder as things go on.
Slavkin: Lilith (Anna Hopkins) drew that mark on both of them, and it was the same identical mark, and it was the way that she was able to bring Jonathan [back to life]. We'll find out the consequences of that mark. It's not just a tattoo, we can promise you that.

Magnus has given up his magic, his immortality, but he's become kind of a staple of the New York Institute. How is he going to be dealing with that loss of power and his loss of ability to help the gang?
Slavkin: What's frustrating is magic has been his rock, and now he doesn't have it and he's used to being the one to solve everyone's problems. "Let's get Magnus to help us!" And now, he's just a normal person, and I think he's got to really struggle through that, and that struggle continues through the entire season. You don't just get over it right away, and obviously that's going to complicate his relationship with Alec and the other people that love him. And Harry Shum is just outstanding. It's such a great performance. It only gets deeper and complicated and twisted as we go on.

Matthew Daddario did tell me last year, that Alec always means well but he is maybe not going to deal with this problem in the best way. Can you tell me anything about his approach to helping Magnus through the identity crisis of sorts?
Slavkin: Alec is a problem solver. He's a guys' guy, where it's like there's an issue of solving you know? And sometimes you just can't solve it. Sometimes it takes time and things get in the way and it's almost like he cares too much and he wants the answer to every question. And that's Alec Lightwood for you, his heart's in the right place, but I think Matt's right when he says that sometimes the decisions he makes aren't always the right decisions and that's part of being a 23-year-old man dealing with a lot.

I did love the peek we got at Asmodeus (Jack Yang) and his history with Magnus in 3A. Is there more of that to come in 3B?
Swimmer: There's more to come and the scenes with Harry and Jack Yang together are really delicious. They're a great pair on the screen and some of the highlights of the season.
Slavkin: We really get into the whole father/son of it all between them, you know? And it's a deep bond and even though Asmodeus has done terrible things to him, it's his father.

It does look like Simon and Izzy might be leaning in for a kiss in that 3B trailer. Are we finally getting Sizzy this season?
Slavkin: Sizzy fans rejoice! It's earned, so it doesn't happen right-- it would be weird if it happened right away because he's with Maya (Alisha Wainwright)... but we're certainly headed in that direction, and I think fans will be happy for sure.

Shadowhunters returns Feb. 25 at 8/7c on Freeform.

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