Agnetha Fältskog: Agnetha Fältskog. Soundtrack: Let the Right One In. Agnetha Fältskog was born on 5 April 1950 in Jönköping, Jönköpings län, Sweden. She is a music artist and actress, known for Let the Right One In (2008), P & B (1983) and Raskenstam (1983). She was previously married to Tomas Sonnenfeld and Björn Ulvaeus.