Any stage production whose advertising tagline is "The Greatest Musical. Ever." doesn't exactly suffer from a lack of confidence. Still, as Dizzy Dean pointed out, it ain't bragging if you can back it up, and few shows can compete with A Chorus Line. A triumphant success from its first off-Broadway performance at Joseph Papp's Public Theater in 1975, the vérité depiction of aspiring song-and-dance performers soon transferred to the Great White Way. Showered with 12 Tony Award nominations, it won nine of them and a Pulitzer Prize for Drama as it kicked off an eye-popping 15-year, 6,137-performance Broadway run. Need we even call it a singular sensation?