Former Misfits star Robert Sheehan, who played Nathan for two seasons on the hit series, has joined the cast of The Mortal Instruments as Simon!

Author Cassandra Clare announced the casting on her Tumblr:

So remember when I said we wouldn’t have a Simon till July for Reasons?

The Reasons were that the actors up for Simon had to test with Jamie and Lily in Toronto to see how the chemistry worked. When I talked to Jamie and Lily yesterday it was about who we thought was the absolute best, the most Simon-y Simon, and fortunately we all agreed.

Y’all know I am a big Misfits fan, so you should not be surprised to know that I’m ecstatic that our Simon is:

Robert Sheehan. You may know him as Nathan.

For any non-Misfits fans out there, Robert Sheehan played Nathan on the hit-UK show, offering much of the comedic relief in the show. Sheehan has also appeared in Cherrybomb alongside Rupert Grint. What do you think of the casting? Is Sheehan a good fit for Simon?