Shadowhunters season 2 to introduce mysterious Sebastian as Clary looks for Jace

Valentine took Jace along with him in season one finale.

Shadowhunters season 2 is returning on Freeform, nine months after the end of season 1. The first season ended with a cliff-hanger after Jace disappears with Valentine in order to protect his friends. The second season will begin with Clary, Alec and Isabelle's quest to find their lost friend.

Click here to watch the show live online on Freeform (only in the US).

The show is set to introduce a major character who will hold equal powers like the antagonist Valentine. Show producers have teased that the new character Sebastian will have layers to his personality.

"If you know the history of the character, you know where he grew up — in hell — and how he was raised. It's important for us to cast somebody who, similarly to Valentine, can embrace that duality," executive producer Matt Hastings told TV Line.

According to Hastings, the character has endured unspeakable torture in hell and his emergence in the shadowhunter's world will be of great significance. "We need someone who can be compassionate, and who may seem like a decent person on the surface. But anybody that's been tortured that much in the bowels of hell by a demon... man, they did terrible things to him. They tore his skin off, layer by layer. That kind of dramatic resonance never goes away from a person, no matter how you shellac it."

However, the show-runner remained silent on whether Sebastian will help Clary in locating Jace or will he be a villain just like Valentine.

"We want to keep the details of how Sebastian emerges on the show ... a little bit close to the vest. He's definitely going to be a charming character with a dark side," said the showrunner Darren Swimmer while teasing that the character will be a fan favourite in the show.

The synopsis of the premiere episode titled This Guilty Blood reads:

Only hours have passed since Jace left with Valentine and all hell has broken loose at The Institute. Alec, Isabelle and Clary are desperate to find Jace, but are quickly stopped in their tracks with the arrival of Victor Aldertree, who means business about getting the Institute back on track. But getting the New York Shadowhunters in-line with The Clave may be counterintuitive to Alec, Isabelle and Clary's plan to rescue Jace. Meanwhile, Jocelyn has a lot to catch up on now that she is awake.

Shadowhunters season 2 premiere episode will air on Monday 2 January at 8pm est on Freeform.

Watch the first five minutes of the show here: