Year Title Role Notes 1974 The Rockford Files Terry Episode: "The Countess" All in the Family Stretch Cunningham 3 episodes Maude Alfie Episode: "Last Tango in Tuckahoe" 1975 Hot l Baltimore Bill Lewis 13 episodes Barbary Coast Roy Episode: "The Ballad of Redwing Jail" 1976–1977 The Nancy Walker Show Glen 13 episodes 1977 Police Story Lutz Episode: "Ice Time" M*A*S*H Captain Leo Bardonaro Episode: "Last Laugh " Three's Company Detective Lannigan Episode: "Chrissy's Night Out" Barney Miller Sgt. Wilkinson Episode: "Group Home" 1978 Maude Dr. Farrington Episode: "The Obscene Phone Call" Alice Detective Ralph Hilton Episode: "Who Ordered the Hot Turkey?" 1979 Barney Miller Neil Spencer Episode: "Strip Joint" Flatbush Sonny Episode: "Kar Kannibals" Eight Is Enough Coach Pollard Episode: "The Better Part of Valor" Diff'rent Strokes Father O'Brien Episode: "Arnold's Hero" The White Shadow Mr. Hamilton Episode: "Mainstream" 1980 Flo Leon Episode: "Homecoming" The White Shadow Art Cummings Episode: "The Death of Me Yet" Little House on the Prairie Harve Miller Episode: "Laura Ingalls Wilder: Part 1 & 2" 1981 Barney Miller Jason Parrish Episode: "Liquidation" 1982 Nurse Paul Moore Episode: "A Place to Die" Father Murphy Farley Webster 2 episodes 1984 Buffalo Bill Staunton McMoller Episode: "Jerry Lewis Week" Gimme a Break! Russell Cosgrove Episode: "Class of '84" 1984–1985 Dallas Gerald Kane 3 episodes 1985 Night Court Alan Episode: "Nuts About Hurry" Family Ties John Hancock Episode: "Philadelphia Story" Riptide Joey Dietz Episode: "Girls Night Out" Hardcastle and McCormick Jake Fellows Episode: "Undercover McCormick" Knight Rider Curtis Episode: "Ten Wheel Trouble" Wildside Fake Buffalo Bill Episode: "Buffalo Who?" Hill Street Blues Lowenhandler Episode: "Grin and Bear It" Hunter Seymour Robbins Episode: "Sniper" The Twilight Zone Obediah Payne Episode: "A Message From Charity " 1985–1986 Scarecrow and Mrs. King Gregory 2 episodes 1986 Amazing Stories Francis Episode: "One for the Road" 1986 Magnum, P.I. French Policeman Episode: "Photo Play" 1986–1987 Easy Street Quentin Standard 22 episodes 1988 China Beach Ambassador Episode: "Pilot" Mr. Belvedere Roy Gallagher Episode: "Fat Cats" Mama's Boy Lucky 3 episodes 1989 Christine Cromwell Arthur Episode: "Things That Go Bump in the Night" 1990 Life Goes On Bill Henderson Episode: "Thacher and Henderson" Matlock Judge Raymond Price Episode: "Nowhere to Turn" 1990-1993 Star Trek: The Next Generation Prime Minister Nayrok/Jaglom Shrek 3 episodes: "The Hunted " and "Birthright Part 1 & 2 " 1991 The Young Riders Jacob Episode: "Peacemakers" Jake and the Fatman Havilland Episode: "It Never Entered My Mind" 1994 L.A. Law Attorney Hutton Episode: "McKenzie, Brackman, Barnum and Bailey" Home Improvement Fred Episode: "My Dinner with Wilson" 1995 Renegade Jeremy Silimen Episode: Stalker's Moon Picket Fences The Bishop Episode: "Saint Zach" Hawkeye Longsworth Episode: "The Visit" Star Trek: Deep Space Nine Hanok Episode: "Starship Down " 1995–1996 Partners Mr. Saxonhouse 2 episodes 1996 Strange Luck Minister Episode: "Healing Hands" The Client Officer Joe Denton Episode: "The High Ground" 2001 ER Bishop Stewart 4 episodes Star Trek: Enterprise Dr. Zefram Cochrane 2 episodes Citizen Baines Senator Elliot Baines 7 episodes; Also Producer 2003 Angels in America Henry 2 episodes 2003–2005 Six Feet Under George Sibley 26 episodes 2004 The West Wing President D. Wire Newman Episode: "The Stormy Present" Salem's Lot Father Donald Callahan 2 episodes 2005 Pope John Paul II Cardinal Adam Stefan Sapieha 2007 24 Phillip Bauer 8 episodes Masters of Science Fiction Randolph Ludwin Episode: "Watchbird" 2008 My Own Worst Enemy Alistar Trumble 6 episodes 2009 Impact Lloyd 2 episodes 2010 Pius XII: Under the Roman Sky Pope Pius XII 2012–2013 Boardwalk Empire Andrew W. Mellon 4 episodes 2012–2013 American Horror Story: Asylum Dr. Arthur Arden/Hans Gruper 10 episodes 2013 Do No Harm Dr. Phillip Carmelo 3 episodes 2013–2014 Betrayal Thatcher Karsten 13 episodes 2014–2015 Murder in the First Warren Daniels 10 episodes 2015 Halt and Catch Fire Jacob Wheeler 8 episodes 2016 The Young Pope Cardinal Michael Spencer 2017–2019 The Detour J.R. 10 episodes 2017 Last Week Tonight with John Oliver Albert B. Fall Episode: "Sinclair Broadcast Group" 2018–2023 Succession Ewan Roy 7 episodes 2018–2020 Big Hero 6: The Series Robert Callaghan / Yokai Voice, 2 episodes [ 2] 2018–2019 Berlin Station Gilbert Dorn 4 episodes 2018–2019 Counterpart Yanek 6 episodes 2019 The Family Douglas Coe 5 episodes 2020 Operation Buffalo General "Cranky" Crankford 6 episodes 2022 Law & Order: Organized Crime Miles Darman 2 episodes Julia John McWilliams Episode: "Boeuf Bourguignon" Star Trek: Lower Decks Holographic Zefram Cochrane (voice) Episode: "Grounded" 2024 Sugar Jonathan Siegel 7 episodes Murder in a Small Town George Wilcox Episode: "The Suspect" 2025 Bat-Fam Alfred Pennyworth (voice) Main role [ 6] 