McMahan, a native of Chicago, first worked in production as an assistant at The Second City. From there, he was hired by Scott Rudin Productions as a production assistant, and worked on Drawn Together and South Park.
McMahan served as a writer and producer on Rick and Morty. He was one of the first writers hired for the series, as he had met co-creator Justin Roiland while working at 20th Century Fox Animation. McMahan described himself as "kind of the sci-fi guy" of the staff, and was promoted to showrunner for the show's fourth season, though he left during production to work on other projects. In 2018, he won the Primetime Emmy Award for Outstanding Animated Program for his work as a supervising producer on the episode "Pickle Rick".
On August 28, 2018, Hulu announced it had ordered an animated comedy Solar Opposites created by McMahan and Roiland. The series premiered on May 8, 2020. In October 2018, McMahan was announced as the creator of Star Trek: Lower Decks for CBS All Access.
- ""Rick and Morty" Writer Mike McMahan Visits New York Film Academy Los Angeles". NYFA Blog. Retrieved May 8, 2020.
- "Staff Interview with Mike McMahan". South Park Studios. Retrieved May 8, 2020.
- Kleinman, Jake. "Rick and Morty's secret weapon is building a "weird" sci-fi empire". Inverse. Retrieved May 8, 2020.
- "Mike McMahan - Emmy Awards, Nominations and Wins". Television Academy. Retrieved May 8, 2020.
- Andreeva, Nellie (August 28, 2018). "Alien Animated Comedy From 'Rick and Morty' Duo & 20th TV Gets Hulu Series Order". Deadline Hollywood. Retrieved August 28, 2018.
- Hipes, Patrick (January 17, 2020). "Hulu Sets Premiere Dates For 'The Great', 'Ramy' And 'Solar Opposites' – TCA". Deadline Hollywood. Retrieved January 17, 2020.
- Goldberg, Lesley (October 25, 2018). "'Star Trek' Animated Comedy a Go With 2-Season Order at CBS All Access". The Hollywood Reporter. Archived from the original on October 25, 2018. Retrieved October 25, 2018.