Anni-Frid Lyndstad was one of the A's in ABBA. She more commonly went by Frida. She still does, I suppose - she's not dead.
She also had one of the biggest post-ABBA solo hits of anyone from the group. Clearly, she made a clear break from ABBA by finding a harder rock sound.... with the help of Phil Collins.... which probably explains the heavy drums. Frida, to her credit, had a huge voice and could easily carry the rock sound just as well as she harmonized with her former bandmates.
As a bonus, here is Frida... er, "live"... performing the song on Swedish television from 1982. I tried to find an actual live performance, but all I could find was lipsynched. Enjoy.