Fans of ABBA have waited YEARS for this, and now the day has finally come for the band to reunite.

Benny and Bjorn celebrated their 50th pal-iversary, and it saw to very special guests in attendance.

Party-goers were absolutely shocked when they saw Agnetha Fältskog and Anni-Frid Lyngstand, ABBA's original members and Benny & Bjorn's former wives, take to the stage to do a performance with their ex-husbands.

Eurovision Song Contest screenwriter and director, Edward af Sillén, caused social media to go into meltdown when he shared this picture of the foursome: