A sweet, naive young woman trying to make it on her own in New York City, Frances doesn't think twice about returning the handbag she finds on the subway to its rightful owner. That owner is an eccentric French piano teacher with a love for classical music and an aching loneliness. Having recently lost her mother, Frances quickly grows closer to the widowed Greta. The two become fast friends, but the older woman's maternal charms begin to dissolve and grow increasingly disturbing as Frances discovers that nothing is what it seems.