Steve Cirbus is an American actor, writer, and director born and raised in western New York, about 40 miles south of Buffalo. His exact birthday and height are not publicly available in major sources. He earned a B.A. in Theatre from Buffalo State College and a Master of Fine Arts in Acting from Ohio University under Barbara Redmond, and spent a year as an artist in residence before embarking on his professional career as a classical actor, performing Shakespeare at some of the oldest and most established festivals and regional theaters on the East Coast and in the Midwest. He later immersed himself in the independent film community in New York City, where he wrote and directed the short film Beat (2005) and Darwin's Privy (2006).

His most notable film credits include Military Police in I Am Legend (2007, with Will Smith), FBI Agent in Salt (2010, with Angelina Jolie), Jeff in Being Flynn (2012, with Paul Dano and Robert De Niro), Reynolds in Syrup (2013), Michael Verona in Bridge of Spies (2015, directed by Steven Spielberg), and Officer Scala in Monsters and Men (2018, with Chris Evans and Monica Barbaro). On television he is best known as Corporal Deke Quinlan in The Kill Point (2007, 8 episodes, TNT), Sergei Mirminski in Delocated (2009–2010, 12 episodes, IFC), Gregor Kasyanov in Gotham (2014), Police Patrolman in The Night Of (2016, HBO, 3 episodes), with additional credits in 30 Rock (2006), Law & Order (2006, 2008), Law & Order: Criminal Intent (2005), The Good Wife (2009), Blue Bloods (2011), Elementary (2012), The Blacklist (2013), Broad City (2019), Quantico (2018), Shades of Blue (2017), FBI (2018, 2025), Monsterland (2020), The Plot Against America (2020, HBO), and Teenage Euthanasia (2021).