Ila (Nimrat Kaur) is an ignored wife, who tries to seek her husband's (Nakul Vaid) attention by feasting him with delicious food, packed in a lunchbox. But instead of reaching to her husband, the meal is handed over to Saajan Fernandez (Irrfan Khan), who is a tedious widower.
Saajan completely cleans the lunchbox, by devouring all the meal. Later, Ila learns that the lunchbox was misplaced. Next day, annoyed Ila sends an arrogant note, accompanied in the lunchbox, to which Saajan readily responds. This leads to routine conversations between the duo, via letters delivered through lunchbox. These strangers tend to share their problems, passion, hope, jokes, by fading the emptiness in each others life.