LIKE HIS LAST FILM, 2003's Salt, writer/director Bradley Rust Gray's The Exploding Girl is a collection of small moments hung on a scrap of narrative. Ivy (Zoe Kazan) is home in New York on her summer break from college. Her longtime friend, Al (Mark Rendall), travels with her, and as Ivy's long-distance relationship with her boyfriend becomes strained, she and Al grow closer.

Those are only a couple dots, and there aren't many more to connect, but Gray isn't aiming for suspense. Girl is an exercise in naturalism first and story second. When Ivy receives a call from her boyfriend telling her he had a small car accident driving with his high school sweetheart, everything remains quiet; Kazan's eyes get a little bigger, sends her best to the girl she doesn't know and returns to sorting her CDs. It would be an easy scene to ruin either through histrionics or by overstating Kazan's stiff-upper-lip reaction, but Gray is neither too aloof nor explanatory.

To be fair, the director's triumph would be nothing without Rendall and Kazan, who imbue their roles with a shared history that's disarmingly natural. Kazan, in particular, gives a great performance, giving scene after scene of quiet, dewy-eyed contemplation through body language alone.

This kind of thing will not be enough for many viewers. With its sleepy, ambling gait, Girl seems a much longer film than its 80 minutes, and those looking for more than keenly observed moments will get restless fast. Anyone happy just watching cute people gazing at their navels, however, would be hard pressed to find a movie this year that does it better.