Harry Shum Jr.
Harry Shum Jr. will play Magnus Bane in ABC family's new fantasy show "Shadowhunters," based on "The Mortal Instruments" book series. Pictured: Shum at the 100th episode celebration of Glee in West Hollywood, California, March 18, 2014 Reuters

“Shadowhunters” is quickly filling out the cast with actors that young fans might recognize. ABC Family announced Alan van Sprang and Harry Shum Jr. have filled the roles of Valentine and Magnus Bane, respectively, on the fantasy drama. They’ll be on opposite sides of the new demon-hunting drama.

Van Spring will be familiar to “Reign” fans as King Henry, and his role as Valentine will be just as power-hungry. Valentine will be the main villain in “Shadowhunters,” and he wants to rule everyone. Even though he is a shadowhunter, an angel-human hybrid that hunts demons, Valentine will kill anyone who gets in his way.

Meanwhile, “Glee” fans will remember Harry Shum Jr. as Mike Chang. While he probably won’t be singing and dancing, he will be just as loveable. Magnus Bane is a fan favorite character for “The Mortal Instruments” readers. If you aren’t one of the millions who have read the young adult book series, you might want to know a little about him.

1. Immortal -- Magnus Bane is the high warlock of Brooklyn. That means he’s very powerful and practices magic. He’s also immortal. Magnus should be at least a few hundred years old, but he’s been known to lie about his age occasionally.

2. Bisexual -- The warlock has only fallen in love a few times over the centuries he’s been alive, but he has fallen for both men and women. The show will feature a romance between Magnus and Alec (Matthew Daddario), a shadowhunter. This is one area where “Shadowhunters” definitely follows Cassandra Clare’s “The Mortal Instruments” book series. The author tweeted she’d been assured the gay love story would stick around.

3. Tortured Romance -- Clare didn’t say if all of the details around Magnus' and Alec’s romance would be the same. If the show follows the young adult book series, Alec won’t exactly be running into Magnus’ arms. Shadowhunters are old fashioned and they don’t really support the LGBT community.

4. Style -- Magnus has a certain fashion sense that definitely sticks out around the shadowhunters, who prefer dark clothing. The warlock is known to rock leather pants, glitter and other attention-grabbing pieces. He can be pretty high maintenance.

5. Troubled Childhood -- A warlock is the child of a demon and a human. Even though Magnus isn’t evil, his human mother and stepfather didn’t accept that he was magical. Without spoiling too much, let’s just say that they didn’t respond well to his powers.

6. Snark -- Magnus knows how to deliver a sassy one-liner. Expect the warlock to provide some comic relief throughout the intense drama. Clare shared that Shum definitely nailed the humorous part of the audition.

ABC Family has not yet announced a premiere date for “Shadowhunters.” Do you think Harry Shum Jr. is a good choice? Sound off in the comments section below!