Suddenly, Last Summer is a play by Tennessee Williams. It opened on Broadway on January 7, 1958 as part of a double-bill with the Williams play Something Unspoken. The presentation of the two plays was given the overall title Garden District, but 'Suddenly Last Summer' is more often performed alone now.

The play tells the story of Catherine, a young woman who seems to go insane after her cousin Sebastian dies on a trip to Europe under mysterious circumstances. Sebastian's mother tries to cloud the truth about her son's homosexuality and his death, whom she wants to be remembered as a great artist. She threatens to lobotomize Catherine for her incoherent utterances relating to Sebastian's demise. Finally, under the influence of a truth serum, Catherine tells the gruesome story of Sebastian's death at the hand of local boys whose sexual favors he sought. Both his mother and later Catherine were only devices for him to attract the young men.

As with many Williams plays, the play incorporates elements from Williams' own life along with elements from the life of his idol, poet Hart Crane. Williams' sister Rose was tragically compelled to undergo a lobotomy at the instigation of their domineering mother.

In 1959 the play was adapted as a movie directed by Joseph L. Mankiewicz, and starring Elizabeth Taylor, Katharine Hepburn, and Montgomery Clift. The screenplay was adapted by Gore Vidal and Williams from his play. The movie was nominated for Academy Awards for Best Actress in a Leading Role (Katharine Hepburn), Best Actress in a Leading Role (Elizabeth Taylor) and Best Art Direction-Set Decoration, Black-and-White.

The play was again adapted for television in 1993 under the direction of Richard Eyre and starring Maggie Smith, Rob Lowe, Richard E. Grant, and Natasha Richardson.