Willow Maclay’s review published on Letterboxd:
Lenny Abrahamson has no instincts. He lets his camera get in close, because he believes that will create intimacy in his subjects. Unlike the Dardennes or even Lynne Ramsay there's an absence of soul in what Abrahamson is trying to convey. In order for ROOM to work you must feel the situation and the characters emotions have to be observed and shot in a way that mirrors their mental state. Brie Larson gives a hell of a performance here, but she is not helped by the workmanlike direction. He knows the tools, but he doesn't know how to use them ya dig?
What you have here is a director who keeps trying to do the same things over and over again, but failing until the film becomes tedious. When Abrahamson reaches for something more lyrical he can't help but get caught up on leaves, because it's easy. When he tries for something sweeping and dramatic he employs slow motion, because it's easy. When he goes for tragedy in suicide (this isn't a spoiler btw), the camera becomes erratic, because it's easy. All of this becomes an unoriginal, easy to please drama, that does absolutely nothing to challenge or engage with the source material past surface level inclinations. This premise is ripe for analysis, and the PTSD and surrounding questions of motherhood should make for a good movie, but all of this is simply grazed over instead of dissected, and only Brie Larson came to play.