From 2005 to 2007 she completed four seasons of Mamma Mia! at renowned venue, Cirkus, in Stockholm. She was a "swing and understudy" in the production, which ment that she learned 6 roles by heart, among them two main characters; mother Donna, and her long-time girlfriend Karin. Every time one of the characters was away, Thérèse got a phone call... For someone as new to theatre as Thérèse, this was the challenge of a lifetime. During the four seasons, she performed the leading part of Donna on more than 30 occasions.

In the Swedish heat of the Eurovision Song Contest she has both participated on her own as a solo artist in 1992, and as a back-up singer and dancer for numerous other acts in the competition. Not to mention the warm-up act before the contests with her "ABBA band", Play, consisting of three additional excellent singers, Micke Grahn, Patrik Lundström and Kristin Stenerhag.