Conor Mclain as Sebastian/Jonathon Morgenstern. He looks like him, doesn't he?
Charlize Theron as Camille Belcourt.
Jodi Lyn O'keefe as Maryse Lightwood.
I love Maryse, she's seemed like a bitch at the beginning but once you read more about her you can tell that she really loves and cares about Jace as much as her own children, and that she'll do anything to protect him, including betraying the Clave
Julianne Moore as Jocelyn Fray.
I like Jocelyn too, you can tell how much she loves and cares for those who she loves, she'll do anything for them. I also liked when Jocelyn went to see the Iron Sisters with Isabelle, it showed that she was strong and still had Shadowhunter-ism left in her, and then when she went to fight to help Clary and Jace with Maryse, Alec, Isabelle, Simon, Magnus and the others, I just really like Jocelyn.
Alex Pettyfer as Jace Wayland Morgenstern Herondale Lightwood. He would just be perfect.
Interesting Fact that annoys me quite a bit: He was the fandom Jace and was offered the role but turned it down
Emma Stone as Clary Fray. I just think she looks like a good Clary. My second choice for her would be Emma Roberts. Just the way she holds herself is how I imagine Clary would.
Phoebe Tonkin as Isabelle Sophia Lightwood. I just love Phoebe, she's my favorite actress and her being Isabelle would just be perfect in my opinion. I can really imagine Phoebe in a lone white dress with an electrum whip.
Logan Lerman as Simon Lewis. I think Logan would make a really cute Simon, don't you?
Chace Crawford as Alexander Gideon Lightwood. I know he's a little old, but I think he'd do well as Alec.
Jessica Kennedy Parker as Maia Roberts. She's just how I imagined Maia, and she's a really good actress.
Drew Roy as Jordan Kyle. He'd just make a good Jordan, well, in my opinion.
This series is written by Cassandra Clare, a very talented amazing writer.