Seamus Patterson (born 6 June 1994; age 30) is an actor and musician who played Cadet Harral in the Star Trek: Discovery fourth season episodes "All Is Possible" and "Coming Home".
In 2015, he appeared in a recurring role on the teenage drama series Degrassi: The Next Generation, which he reprised in the TV movie Degrassi: Don't Look Back in the same year. Both projects featured Patterson's "All Is Possible" castmate Amanda Arcuri and Star Trek: Strange New Worlds actor André Dae Kim in the main cast.
Also in 2015, Patterson had a regular role in the first season of This Life, alongside Shawn Doyle. The next year, he had a recurring role in Reign, starring Adelaide Kane and featuring Dan Jeannotte, Jonathan Goad, and Kyle Gatehouse.
He appeared in guest roles on series such as Saving Hope (starring Huse Madhavji, with Milton Barnes), Murdoch Mysteries, Shadowhunters (with Harry Shum, Jr., Romaine Waite, and Wole Daramola), Coroner (starring Roger Cross, with Saad Siddiqui), and Guillermo del Toro's Cabinet of Curiosities (with Thom Marriott).