Many critics believe that The Night of the Iguana was Tennessee Williams's last great play. Howard Taubman of the New York Times writes, "For Mr. Williams, The Night of the Iguana marks a turning point. When compared with the best of the preceding plays, this work of subtle vibrations reflects a profound change. It goes beyond the elimination of the explosive and shocking gestures, which have given some of the other works the fillip of being sensational and scandalous, and reaches into the playwright's attitude towards life." A concurring critic, Harold Clurman of The Nation, finds Williams's writing to be superb. He says, "The writing ... is lambent, fluid, malleable and colloquially melodious. It bathes everything in glamour."

Numerous critics believe the character of Hannah is key to the play's success. An unnamed critic in Life argues, "The Night of the Iguana is Williams's best play in...