Mature character actress who specialized in portraying aristocrats and wealthy society matrons. Although Landis appeared in over 45 plays on the Broadway and London stage and made her film debut in 1930, it was not until the 1950s that she gave her most notable film performances. She was twice cast as the mother of Grace Kelly--in Alfred Hitchcock's "To Catch a Thief" (1955), as the caustic mother who stubs out her cigarette in a soft-boiled egg, and again in "The Swan" (1956). Landis also played Cary Grant's sophisticated mother in "North By Northwest" (1959), although she was ten months younger than him.