Born in St. Petersburg, Russia, Greta Onieogou emigrated to Canada with her family when she was 5 years old. Always a performer, Onieogou was initially interested in pursuing competitive rhythmic gymnastics, but acting quickly took hold. Her first onscreen credit came in the romantic comedy "Fever Pitch" (2005) starring Drew Barrymore and Jimmy Fallon, followed by guest spots on the Canadian series "Degrassi: The Next Generation" (CTV, 2001-09; MuchMusic, 2010-13; MTV Canada, 2013-15), and "Naturally Sadie" (Family Channel, 2005-07). Onieogou landed her first recurring role on the series "Heartland" (CBC, 2007-), playing the best friend of the lead character for the first five seasons of the show. In 2015, Onieogou was a series regular on the web series "Heroes Reborn: Dark Matters" (NBC, 2015), a companion to the network series "Heroes Reborn" (NBC, 2015-16), itself a sequel to the hit show "Heroes" (NBC, 2006-2010). After a small role in the film "Miss Sloane" (2016), she appeared in guest roles on a number of series, including "Schitt's Creek" (CBC, 2015-), "Murdoch Mysteries" (City, 2008-2012; CBC, 2013-), and "Anne with an E" (CBC, Netflix, 2017-). In 2018, it was announced that Onieogou would be a series regular on "All American" (The CW, 2018-) a drama following a football player in South Central Los Angeles who is recruited to play at Beverly Hills High School.