José Ferrer asked Lansing to perform in a series of plays at the New York City Center, including as a Cadet of Gascoyne in "Cyrano de Bergerac" and as the Marquis of Dorset in "Richard III". He appeared in Tennessee Williams' "Suddenly, Last Summer" and Eugene O'Neill's "The Great God Brown" in the title role. Other stage performances included roles in Charley's Aunt, Elmer Rice's "Cue for Passion", "The Lovers", and "The Cut of the Axe". Off-Broadway, his work included "The Father", the "Sea Plays" of Eugene O'Neill and two one-man shows, "Damien" and "The Disciple of Discontent".