He was known for his role as Eric Green in the CBS television series Jericho (2006–2008) and for portraying various characters in Star Trek: Discovery (2017–2021).

[1] He attended Earl Haig Secondary School in his hometown, before studying landscape architecture at the University of Guelph.

[3] Mitchell appeared as Eric Green in the U.S. television drama Jericho, which was cancelled by CBS in May 2007, but was brought back onto the 2007–08 schedule following a fan campaign to save the show.

[4] In 2014, Mitchell was cast in ABC's The Astronaut Wives Club television drama series, playing the role of Deke Slayton.

[2] In February 2020, Mitchell revealed that he had been diagnosed with amyotrophic lateral sclerosis (ALS), also known as Lou Gehrig's disease.