A New York high-school student feels certain that she played a role in a traffic accident that has claimed a woman's life. In her attempts to set things right, she's met with opposition at every step.

Critic Reviews:

• " Anna Paquin offers one of the more indelible portraits of late adolescence put on screen. " – Josh Larsen (LarsenOnFilm)

• " Knotty, ambitious and trading in messy human truths, it's the work of a master dramatist. Here's hoping Lonergan's next one reaches us a little faster. " – Guy Lodge (Empire Magazine)

• " Margaret is less about plot mechanics than about the virtuosity of the dialogue, the complexity of the characters, and the detail and depth of their untidy world. " – Nicholas Barber (Independent, UK)