Niagara Niagara (1998)

Is Tourette's syndrome a neurobiological ''disease'' or a disorder of the spirit? The best thing about Robin Tunney's performance in Niagara Niagara as Marcy, a troubled young upstart who suffers from the enigmatic condition, is the way she suggests that it may be both. Marcy's tics and spasms can look like simple nerve disorders, but when she spews out a rush of invective or fires a machine-gun blast of unconscious feelings about someone directly into his or her face, she seems to be cutting to levels of rage and truth her own body won't let her express — or even feel — otherwise. Tunney has a curlicued sexiness that recalls the young Margot Kidder, and she gives a compelling performance that, unfortunately, can scarcely hold down the center of a dodderingly flat and aimless road movie (at this point, is there any other kind?). The actress is paired with Henry Thomas (yes, that Henry Thomas), cast as a doleful-eyed misfit dreamer who's pretty but has nothing of interest to say. The film keeps slipping into inertia, but just when you've given up on it, Tunney's Marcy, with her cherry-bomb instability, gooses it alive. C+