'Mamma Mia!' (2001)
Some of these musicals on our list have been downright dark, so it's not surprising that "Mamma Mia!" was welcomed with open arms, helping to kick-start an entirely new genre, the jukebox musical (a musical featuring well-established songs, usually from a famous pop singer or group) [source: Ellen]. Not only is the plot full of whimsy — a daughter tries to figure out which of three men is her biological father, amid much singing and dancing, naturally — "Mamma Mia!" is also set to the music of beloved '70s group, ABBA. Songs like "Dancing Queen" and "Take a Chance on Me" served to create a nostalgic production for disco-lovers of the past, while also introducing the score to an entirely new generation [source: Broadway in Chicago].
So successful was the Broadway run, that "Mamma Mia!" became a major motion picture in 2008 starring Meryl Streep and Amanda Seyfried. It has since inspired a number of other jukebox musicals, like "Jersey Boys" (featuring the music of the Frankie Valli and the Four Seasons), "Movin' Out" (songs courtesy of Billy Joel) and "Motown: The Musical" (no explanation needed, hopefully).