Marc Bruni directs the evening that features musical tributes, readings and clips from Plummer's lengthy career on stage. His colleagues will also offer tributes during the 6:30 PM event at the Edison Ballroom. O'Neill executive director Preston Whiteway and chairman Tom Viertel host the evening.
Spacey (Richard III, "American Beauty") was honored with the Monte Cristo Award in 2009.
A two-time Tony Award winner for Cyrano and Barrymore, and beloved for the film of "The Sound of Music," Plummer is being honored for "his monumental achievements and contributions to the American and international theatre community."
Plummer is an Academy Award winner for "Beginners." He also portrayed James Tyrone from Long Day's Journey Into Night for a PBS American Masters documentary of Eugene O'Neill.
Previous Monte Cristo recipients include Michael Douglas, James Earl Jones, Harold Prince, Neil Simon, Jason Robards, Jr., Edward Albee, August Wilson, Zoe Caldwell, Brian Dennehy, Karl Malden, Arthur & Barbara Gelb and Wendy Wasserstein.