Wow who would have thought?

Björn, Benny, Agnetha and Anni-Frid’s surprise appearance marks the first time that the group have appeared on stage together in public in 30 years. Their final public performance was aired on Swedish television in January 1986, when they performed an acoustic version of ‘Tivedshambo’ as part of a 55th-birthday celebration of their manager, Stig Anderson; later that year they also performed at a private 40th-birthday party for their old manager, Claes af Geijerstam. 

ABBA launch the new venture the same year that one of their most iconic singles, ‘Dancing Queen’, turns 40.

Taken from their Arrival album and released in August 1976, it topped the charts in nine countries.

Whether the group – one of the most beloved in music history – have any more surprises in store for the anniversary of one of their signature songs remains to be seen; meanwhile, the opening of Mamma Mia! The Party is sure to send ABBA’s dedicated fan base into a frenzy.