The Good Sister follows a couple who is working to put their crumbling marriage back together, when the wife receives a letter informing her that she has a long-lost twin sister. First thinking that the new family member will bring the couple closer together, the husband then begins an affair with the sister and discovers that she is treacherous and dangerous.
Sonya Walger
as Kate / Linda
Ben Bass
as Jack McLennan
Bobbie Phillips
as Mrs. Nelles
Ashleigh Harrington
as Cassie
Alarey Alsip
as Deb
Michael Hearn
as Walberg
Noel Burton
as Langler
Sam Stone
as Cab Driver
Emma Dimig
as Twin Girl #1
Sonia D'amico
as Twin Girl #2
Howard Harris
as Older Man
Simon Anthony
as Police Officer
