“Blackbird” assembles a terrific cast in the service of fairly mundane movie — a small-boned production about a woman facing a terminal diagnosis, summoning her family to say goodbye. The premise and performers yield some emotional moments, inadvertently heightened by recent events. Yet as a whole, the film never quite takes wing.
Susan Sarandon is Lily, whose shuffling, strenuous effort just to get up and down the stairs reveal the way that ALS is ravaging her body. Before the condition worsens, she plans to quietly take her own life with the help of her husband (Sam Neill), but not before spending the weekend in their idyllic beach house with her family.