Johnson's major directorial debut was the independent mockumentary-sitcom web series Nirvana the Band the Show, which ran from 2007-2009.

[15][16] Peter Debruge of Variety wrote, "Matt Johnson and Owen Williams' wild, borderline-illegal stunt delivers big time on its crazy premise.

[22] In 2022, Johnson directed and co-wrote, with Matthew Miller, the film BlackBerry, about the rise and fall of Canadian tech company Research in Motion.

[23] The film stars Glenn Howerton as Jim Balsillie, Jay Baruchel as Mike Lazaridis, and Johnson as Douglas Fregin.

[24] BlackBerry premiered in competition at the 73rd Berlin International Film Festival on February 17, 2023,[3] and attracted widespread critical acclaim.

[27] In addition to his own productions, he has had acting roles in feature films such as Diamond Tongues, and the Kazik Radwanski projects How Heavy This Hammer, Anne at 13,000 Ft. and Matt and Mara.

Johnson and Jay McCarrol co-created and co-starred in an animated spiritual successor to Nirvanna the Band the Show made for children called Matt & Bird Break Loose in 2021.