John Marcus "Scoot" McNairy (born November 11, 1977) is an American actor and film producer. He is known for his roles in films such as Monsters (2010), Argo, Killing Them Softly (both 2012), Batman v Superman: Dawn of Justice (2016), Speak No Evil, and Nightbitch (both 2024).

On television, McNairy starred as Gordon Clark in the AMC period drama Halt and Catch Fire (2014–2017), Bill McNue in the Netflix miniseries Godless(2017), Walt Breslin on Netflix's Narcos: Mexico (2018–2021), Tom Purcell on the third season of True Detective (2019), and Rod Rosenstein in the Showtime miniseries The Comey Rule (2020). His accolades include an Independent Spirit Award and a Screen Actors Guild Award.