Markell served four years with 2nd Battalion, 5th Marines. Markell worked in the boat company specializing in clandestine operations with Zodiac boats. Another specialty of his was "assault climber"; essentially, tactical rock climbing and rappelling. He is a third award rifle expert and broke two records for 9mm while he participated in the "Fleet Assistance Program" with Military Police for six months. He earned an honorable discharge at the end of his time.
Markell had to learn Hebrew for his role in Baram & Hamza, 2010.