For Disney, he voiced Charles F. Muntz in the 2009 Disney/Pixar film, Up and the narrator of the Madeline franchise and played John Adams Gates in National Treasure, Mr. Massie in the Touchstone Pictures film, Cold Creek Manor, and Abraham Van Helsing in the Miramax film, Dracula 2000.
- He was originally considered for the role of Ego in Guardians of the Galaxy Vol. 2, but in the end, Kurt Russell was cast instead.
- Plummer was once considered for the role of Bert in Mary Poppins along with Danny Kaye, Fred Astaire, Jim Dale, Cary Grant, Richard Burton, Alec Guinness, Richard Harris, Rex Harrison, Ron Moody, Frank Sinatra, Laurence Olivier, Peter O'Toole, Gregory Peck, Peter Lawford, Kirk Douglas, James Garner, Michael Rennie, Phil Harris, Buddy Ebsen, Sean Connery, Peter Sellers, Richard Todd, Tommy Steele, Peter Ustinov, David Niven, and Roddy McDowall.
- He was once considered for the role of Professor Emelius Browne in Bedknobs and Broomsticks along with Peter Ustinov, David Niven, Ron Moody, Gene Hackman, Zero Mostel, Dennis Hopper, Don Knotts and Tim Conway.