Frequent Stargate SG-1 guest star Dion Johnstone is headed to Syfy’s next big original series.  The actor has been cast in a recurring role on Defiance, set to premiere in April.

Johnstone will play an alien “spirit rider” named Nizar in three episodes.

“Having a great time back on the set of Defiance,” the actor recently tweeted. “Have shot a few scenes already with the dialogue almost fully in alien. Super cool!”

The series (which will be tied in with the MMO-RPG of the same name) is set in a frontier town populated by both humans and alien species after an alien ark crashes on Earth, leaving the planet transformed.  An alien species called the Votans are among those seeking a new home on Earth after their world is destroyed.

Defiance stars Grant Bowler, Julie Benz, Tony Curran, Jaime Murray, and Stephanie Leonidas.

Johnstone played several roles on SG-1 both with and without prosthetics, including Chaka (“The First Ones,” “Beast of Burden”), Lt. Tyler (“The Fifth Man”), Captain Nelson (“Rules of Engagement”), and Warrick (“Forsaken”).

In addition to his turn on Defiance, Johnstone can be seen in guest roles on Canada’s Flashpoint and Cracked.  He’ll then head back to the stage to play Marc Antony in the Chicago Shakespeare Theatre production of Julius Caesar in February and March, 2013.

Check out Johnstone’s official Web site at DionJohnstone.com, and follow him on Twitter @DionJohnstone.