In 1996, Hillingsø appeared in Peter Thorsboe's drama, Krystalbarnet in which she starred with Mirosław Baka, Grażyna Barszczewska and Helene Egelund. In 1999 she starred in Søren Kragh-Jacobsen's Mifune's Last Song alongside Iben Hjejle, Anders Hove, Sofie Gråbøl and Paprika Steen. In 2007 she appeared in Karlas kabale, based on the 2003 book of the same title written by Renée Simonsen. Also in 2007 she starred in the Danish television police drama, Anna Pihl.