Born in Troy, NY; educated at Siena College, Herbert Berghof Stuios and the Actors Studio, New York. Earthy character player who first attracted attention for her portrayal of the Tennessee Williams heroine in The Rose Tattoo on Broadway in the early 1950s. She appeared on Broadway from 1946 until 1981. Stapleton made an acclaimed film debut in LONELYHEARTS (1958), an adaptation of Nathanael West's book, and gave effective, wide-ranging performances in films including THE FUGITIVE KIND (1959), INTERIORS (1978) and REDS (1981) and the affecting TV movie, "Queen of the Stardust Ballroom" (1975). Other notable unnominated screen credits include BYE BYE BIRDIE (1963), PLAZA SUITE (1971), LOST AND FOUND and THE RUNNER STUMBLES (both 1979), THE FAN (1981), JOHNNY DANGEROUSLY (1984), COCOON (1985), THE MONEY PIT and HEARTBURN (both 1986), SWEET LORRAINE and NUTS (both 1987), COCOON: THE RETURN (1988), PASSED AWAY (1992), DRADING MOM (1994), ADDICTED TO LOVE (1997), WILBUR FALLS (1998) and LIVING AND DINING (2003). She also appeared in many made-for-television movies. At the Oscar® ceremonies in 1982, Ms. Stapleton became the fourth of four consecutive winners of the Best Supporting Actress award to have the initials "M.S.". The others are: Maggie Smith (CALIFORNIA SUITE, 1978), Meryl Streep (KRAMER VS. KRAMER, 1979) and Mary Steenburgen (MELVIN AND HOWARD, 1980). In her 1995 autobiography, Hell of a Life, she famously remarked: "I've been asked repeatedly what the 'key' to acting is, and as far as I'm concerned, the main thing is to keep the audience awake."  Nominated for Supporting Actress 1958: LONELYHEARTS  Nominated for Supporting Actress 1970: AIRPORT  Nominated for Supporting Actress 1978: INTERIORS  Supporting Actress 1981: REDS 4 nominations, 1 Award