Acting · Plainfield, New Jersey, USA · Born February 8, 1969
Mary Catherine McCormack is an American actress. She has had leading roles as Justine Appleton on the series Murder One (1995–1997), as Deputy National Security Adviser Kate Harper on The West Wing (2004–2006), as Deputy U.S. Marshal Mary Shannon on In Plain Sight (2008–2012), and as Peggy on the comedy series The Kids Are Alright (2018–2019).
MovieVicious
2025
as Mother
TVThe Pitt
2025
as Dr. Linda Conley
MovieNational Memorial Day Concert
2023
as Self
TVHeels
2021
as Willie Day
MovieUnpregnant
2020
as Debra Clarke
TVThe L Word: Generation Q
2019
as Anne Finley
MovieStill Laugh-In: The Stars Celebrate
2019
as Self
MovieTreehouse
2019
as Lilith
TVThe Kids Are Alright
2018
as Peggy Cleary
TV25 Words or Less
2018
as Self
TVFor the People
2018
as Chloe Daniels
TVWill & Grace
2017
as Janet
MovieDrone
2017
as Ellen
TVLoaded
2017
as Casey
MovieAlien Code
2017
as Rebecca
MovieThe Crash
2017
as Sarah Schwab
MovieAn American Girl Story: Maryellen 1955 - Extraordinary Christmas
2016
as Kay Larkin
TVDivorce
2016
as Kathy DeSantis
TVMatch Game
2016
as Self - Panelist
TVTo Tell the Truth
2016
as Self - Panelist
TVChelsea
2016
as Self
MovieA Country Called Home
2016
as Amanda
TVChelsea Does
2016
as Herself
TVAngie Tribeca
2016
as Abigail Liukin
MovieScooby-Doo! WrestleMania Mystery
2014
as Ms. Richards (voice)
TVWelcome to the Family
2013
as Caroline Yoder
MovieEscape from Polygamy
2013
as Leann
TVThe Newsroom
2012
as Molly Levy
MovieShould've Been Romeo
2012
as Ellen
TVScandal
2012
as Lisa Elliot
TVHouse of Lies
2012
as Denna Altshuler
The Unprofessional
2012
as Hilary Pfeiffer-Dunne
TVWatch What Happens Live with Andy Cohen
2009
as Self - Guest
TVLate Night with Jimmy Fallon
2009
as Self
TVIn Plain Sight
2008
as Mary Shannon
Movie1408
2007
as Lilly Enslin
MovieFor Your Consideration
2006
as Pilgrim Woman
MovieRight at Your Door
2006
as Lexi
MovieMadison
2005
as Bonnie McCormick
TVThe Late Late Show with Craig Ferguson
2005
as Self
TVTraffic
2004
as Carole McKay
TVK Street
2003
as Maggie Morris
TVThe Ellen DeGeneres Show
2003
as Self
MovieDickie Roberts: Former Child Star
2003
as Grace Finney
TVJimmy Kimmel Live!
2003
as Self
MovieFull Frontal
2002
as Linda
MovieWorld Traveler
2002
as Margaret
MovieK-PAX
2001
as Rachel Powell
TVLaw & Order: Criminal Intent
2001
as Mary Shannon
MovieHigh Heels and Low Lifes
2001
as Frances
MovieBigLove
2001
as Phoebe
East of A
2000
as Daphne
MovieGun Shy
2000
as Gloria Nesstra
MovieThe Broken Hearts Club: A Romantic Comedy
2000
as Anne
MovieOther Voices
2000
as Anna
MovieThe Big Tease
1999
as Monique
MovieMystery, Alaska
1999
as Donna Biebe
TVThe West Wing
1999
as Kate Harper
TVThe Late Late Show with Craig Kilborn
1999
as Self - Guest
MovieTrue Crime
1999
as Michelle Ziegler
MovieHarvest
1999
as Agent Becka Anslinger
MovieGetting to Know You
1999
as Leila Lee
MovieThe Alarmist
1998
as Sally
Movie54
1998
as New Year's Eve Wife (uncredited)
MovieDeep Impact
1998
as Andrea Baker
MovieMurder One: Diary of a Serial Killer
1997
as Justine Appleton
MovieFathers' Day
1997
as Virginia Farrell (uncredited)
MoviePrivate Parts
1997
as Alison Stern
MovieColin Fitz
1997
as Moira
TVMurder One
1995
as Justine Appleton
TVThe Wright Verdicts
1995
as Beth Eckhart
MovieBackfire!
1995
as Sarah
MovieMiracle on 34th Street
1994
as Myrna Foy
TVER
1994
as Debbie
TVThe Tonight Show with Jay Leno
1992
TVLaw & Order
1990
as Rickie the Bartender
TVTony Awards
1956
as Self - Nominee
