Ryan got his start in television when he entered and won the Norman Lear Playwriting award sponsored by Columbia Pictures Television (which later became Sony). The award included a $25,000 cash gift and meetings with Columbia's top television producers. Later he was a staff writer on the show Nash Bridges and served as a writer/producer on Angel before creating and acting as Head Writer on The Shield. He was partnered with David Mamet to serve as showrunner for The Unit.
Ryan was set to executive produce Confessions of a Contractor, a 2009 CBStelevision pilot based on Richard Murphy's book of the same name. The story centres on a successful L.A. contractor who becomes involved with two of his female clients. The production was put on hold when casting contingencies could not be met. He was the show runner for season 2 of Fox's Lie to Me. He was the show runner and executive producer of FX's Terriers. He created the crime drama The Chicago Code. In 2012, Ryan's pilot Last Resort got picked up by ABC for the fall. On November 21, 2012, it was announced that producers had been given enough notice of the network's plans not to pick the show up for a full season and that they were reworking the final episode to function as a series finale and give the fans closure.
On January 2013, CBS picked up Beverly Hills Cop, an hourlong crime procedural with comedic elements, with Ryan on board to pen the script and executive produce along with his MiddKid Productions partner Marney Hochman and Eddie Murphy. The potential series is a follow-up to the Murphy franchise and centers on Foley's son, Aaron (played by Brandon T. Jackson), a cop working in Beverly Hills as he does his part to escape his famous father's shadow. Murphy will reprise his role as the wisecracking detective in the pilot and would recur should the project go to series.Barry Sonnenfeld will direct the pilot. In May 2013, the show was not picked up by CBS.