IFC Films has unveiled theatrical trailer for An Invisible Sign (2011). "An Invisible Sign of My Own" is a coming-of-age drama based on Aimee Bender's quirky novel about a 20-year-old loner named Mona Gray (Alba) who as a child turned to math for salvation after her father became ill. As an adult, Gray now teaches the subject and must help her students through their own crises. Watch theatrical trailer now!