Hörbiger descends from a famous Austrian family of actors and actresses, all at least for some times members of Austria's National Theatre, the Burgtheater.

Mavie had theatre engagements in Hanover and Bochum (Rachel in Sanft und grausam, 2006; Jeannie in Fettes Schwein, 2005; title role in Lulu, 2004; Gilda in Komödie der Verführung, 2002; Santuzza in Freunde II, 2001).

From 2006 to 2008 she performs at the Theater Basel, her first role there being "Roxane" in the play Cyrano de Bergerac, followed by "Stella" in A Streetcar Named Desire.

In 2015, Hörbiger claimed two major successes at the Burgtheater, first in Tolstoj's The Power of Darkness, then as Ismene in Antigone by Sophocles.

In 2004, she ranked third in the voting for the 100 Sexiest Women In The World held by the German edition of FHM magazine, just behind Britney Spears and Heidi Klum.