[1] Hornstra began her acting career in 1993, appearing in a short film titled The Door.
She gained recognition for her leading role as 'Tatyana 'Tats' Alecsandri' in Sweat, a drama series set in an athletic school.
Following Sweat, Hornstra had a recurring role as 'Allie Matts' on teen television series Heartbreak High for two seasons.
From 2002 to 2006, Hornstra had a recurring role on popular series McLeod's Daughters, as 'Sandra Kinsella' (later Kinsella-Ryan).
Other credits include medical drama series G.P., Big Sky, Murder Call, Wildside, Water Rats, Head Start, BeastMaster, and Farscape; and the television films Chameleon, which aired on UPN in 1998, BlackJack: Murder Archive and BlackJack: Ace Point Game.