World reference of the disco with 400 million albums sold, unforgettable titles like Waterloo, Mamma Mia ! or Dancing Queen, ABBA is a real planetary success. For 50 years, the world has been dancing to the rhythm of this mythical group. One year after the release of their new album, Agnetha, Björn, Benny and Anni-Frid meet again in a documentary that retraces the recipe of their incredible longevity. Between musicals, movies and concerts with their holograms, ABBA reveals the secret of their eternity.