ELSEWHERE IN THIS WEEK'S Film section, you're going to find reviews that throw great fistfuls of praise at Viola Davis (Lila & Eve) and Ian McKellen (Mr. Holmes). And—spoiler—this review's going to throw great fistfuls of actorly praise around too, in this case at Mark Ruffalo and Zoe Saldana. Both might be best known, weirdly enough, for being buried beneath terabytes of pixels—Ruffalo as The Avengers' Hulk, Saldana as Avatar's blue alien cat-warrior-thing—but here they're visible in the flesh, without any explosions exploding around them. Well, unless you count the outbursts of Cameron (Ruffalo), who's trying to raise two daughters while also dealing with bipolar disorder. Those are kind of explosions.

Written and directed by Maya Forbes—and based on her own childhood—Infinitely Polar Bear is an excellent example of why story matters more than plot. Unlike the overstuffed blockbusters its stars sometimes appear in, Infinitely Polar Bear is stripped down and focused, letting the characters' thoughts and hopes become ours. When Maggie (Saldana) moves to New York for graduate school, she leaves her daughters (played by Ashley Aufderheide and Forbes' daughter, Imogene Wolodarsky) with her semi-estranged husband, Cameron—giving Cameron two major responsibilities that, with his mood swings and ping-ponging focus, he may or may not be up for. The resulting story spans days, then weeks, then months: Cameron tries, Cameron succeeds; Cameron tries, Cameron fails. Everybody's trying to do their best. Sometimes their best isn't good enough.

Forbes balances the tone just right—never too light and never too dark, the story always feels real—but Ruffalo and Saldana steal the film, with Ruffalo's goofy charm giving way to angry frustration as Saldana's determined pragmatism buttresses her world-weary optimism. There's love in this family, but there's also all the other stuff families have to deal with: money, work, illness, race, time apart, time together. It's a pretty great family. It's a pretty great movie.