John O'Brien
Actor
Active 1993–present
Filmography
Friends (1994) - Airline EmployeeGrey's Anatomy (2005) - Lab Tech JeffreyMalcolm in the Middle (2000) - Sales ClerkCriminal Minds (2005) - Dr. MeyerThe X-Files (1993) - Missionary #2Shameless (2011) - Father Monroe9-1-1 (2018) - Rod BillingsPretty Little Liars (2010) - Principal HackettTwo and a Half Men (2003) - WaiterVictorious (2010) - Mr. MooneyCommunity (2009) - ChaplinDesperate Housewives (2004) - Dr. WheelerNCIS (2003) - BruceMad Men (2007) - Phil KennedyS.W.A.T. (2017) - WeberMonk (2002) - Maitre'dChuck (2007) - Older CIA TechThe West Wing (1999) - ReporterSuperstore (2015) - MikeMedium (2005) - Hotel ClerkEnough (2002) - Front Desk ClerkMom (2013) - WaiterBoston Legal (2004) - Clerk #2Hacks (2021) - Duncan