He graduated in 2002 with a film degree from Wesleyan University where he served as President of the Eclectic Society.
Whedon joined the crew of the HBO western drama Deadwood as an assistant to executive Producer David Milch for the first season in 2004. The series was created by Milch and focused on a growing town in the American West. Whedon returned as Milch's assistant for the second season in 2005. He also became a Writer for the third and final season in 2006 when he co-wrote the episode "Amateur Night" with writer's assistant Nick Towne. Whedon and the writing staff were nominated for a Writers Guild of America Award for Outstanding Drama Series at the February 2007 ceremony for their work on the third season.
In Jan 2014, Dark Horse Comics released Serenity: Leaves on the Wind, a six-issue comic book series written by Whedon with art by Georges Jeanty that continues the story of brother Joss's cult television show Firefly, and its subsequent film adaptation Serenity. The comic is also executive produced by Joss Whedon and continues the story roughly 39 weeks after the events of the film. He is also a Producer of the SundanceTV drama The Red Road and the AMC drama Halt and Catch Fire.