A deceased woman's diaries reveal secrets that threaten her best friend's relationships when she can't resist reading them, despite warnings.

Mariel, a homemaker who died of cancer, left a box full of her diaries over the years to her best friend Carly, an advertising executive. Sandra and Olive warn her not to read them, but she can't resist wanting to know what Mariel had written. Soon, all the hidden stories ruin their friendship.